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Bernoulli
heat
Optics
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Quantum
Physics Problems with Answers and Solutions
mechanics, kinematics
Your car starts from rest and accelerates to 60 miles per hour in 6 seconds. How far did your car travel in meters? How about in feet?
Answer: d = 80.5m = 264 ft
Solver Input: vi=0,vf=60mi/h,t=6,d=?,d=?ft
Tutorial video:
mechanics, projectiles
A projectile is fired with an angle of 45 degrees above the horizontal at a speed of 15m/s. If the projectile lands 2 m above its starting position, how far did the projectile travel? How about if it landed at the same level it started off at? What is the maximum height the projectile achieves?
Answer: at dy=2, dx= 20.7. At dy=0, dx=22.9. dy at maximum (when vfy=0) is 5.7 m
Solver Input: theta_vi=45,vi=15,dy=2, dx=?
Tutorial video:
mechanics, force
Neo applies a constant force to a 20g bullet travelling at 500m/s, and stops it in 1 millisecond. Find the force.
Answer: F_applied = -10000N
Solver Input: vi=500,m=20g,t=1ms,F_applied=?,vf=0
Tutorial video:
mechanics, slopes
A 20kg block accelerates down an inclined slope of 30 degrees at a rate of 2.4 m/s^2, what is the kinetic coefficient of the slope's surface?
Answer: uk = 0.29
Solver Input: theta_slope=30,m=20,a=-2.4,uk=?
Tutorial video:
mechanics, slopes
You push horizontally (not along the slope) on a 25 kg mass up a slope of 40 degrees with 500 N. The slope's surface has a coefficient of friction of 0.41. What is the resulting acceleration of the mass?
Answer: a = 0.66
Solver Input: F_applied_x=500,m=25,theta_slope=40,uk=0.41,a=?
Tutorial video:
mechanics, slopes
A 200 pound man sits on a slide with a 45 degree angle of incline. The slide has an 0.3 coefficient of friction. How fast will he accelerate?
Answer: a=-4.86m/s^2 (negative because he's sliding down the slope)
Solver Input: theta_slope=45,m=200lb,uk=0.3,a=?
Tutorial video:
Click here to see tutorial
mechanics, force
A rope pulls a 20kg sled across ice. The rope makes an angle of 45 degrees to the ground, and the tension in the rope is 100 Newton. What is the acceleration of the sled?
Answer: ax = 3.54m/s^2
Solver Input: m=20,theta_F_applied=45,F_applied=100,ax=?
Tutorial video:
Click here to see tutorial
mechanics, energy
You push on a block with 135 Newton of force through a distance of 246 meters. How much work did you perform?
Answer: W = 33210
Solver Input: F_applied=135,d=246,W=?
Tutorial video:
Click here to see tutorial
mechanics, energy
You pull on a box with 135 Newton using a rope that makes an angle of 45 degrees with the horizontal. How much work did you do if you pulled the box for 246 meters?
Answer: W = 23483 J
Solver Input: F_applied=135,d=246,theta_F_applied_d=45,W=?
Tutorial video:
Click here to see tutorial
mechanics, energy
A one Ton car can accelerate from 0 to 60 mph in 6 seconds. How much horsepower does the car have?
Answer: W = 59953 W = 80 hp
Solver Input: m=1tonne,P=?hp,vi=0,vf=60mph,t=6
Tutorial video:
Click here to see tutorial
collisions
A 2.72 kg ball travels at 9.81 m/s, a 3.14 kg ball travels in the opposite direction at 8.31 m/s. They collide head on. After the collision, the 2.72 kg ball rebounds with a speed of 8 m/s. What is the speed of the other ball?
Answer: 7.12 m/s
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
collisions
m1 (1g) travels east at 3 ft/s. m2 (1.2g) travels west at 4 ft/s. After they collide, m1 travels at 2.5 ft/s, 30 degrees south of east. Find the speed and direction of m2 (in ft/s).
Answer: v=3.46 ft/s, theta is 17 degrees N or W (163 degrees CCW)
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
collisions
At a family reunion, Chef meets Marathon, his long lost brother. Crying and hollering, a 400 pound Chef charges at his brother with a speed of 5 m/s. Marathon, weighing 120 pounds, sprints toward his brother at a speed of 9 m/s. Chef and Marathon collide and stick together in an embrace of love. Find the resultant velocity.
Answer: 1.77 m/s
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
collisions
A neutron is at rest and has a mass of 1.67e-27 kg. Suddenly, it emits an electron with a mass of 9.1e-31 kg, travelling at 1.6e+8 m/s. At what speed does the remaining proton recoil?
Answer: 87233 m/s
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
collisions
Two balls travel toward each other. One has a mass of 2.46 kg, and a velocity of 3.21 m/s. The other has a mass of 6.42 kg, and a velocity of 1.23 m/s. They collide in a perfectly elastic collision. Find their velocities after the collision.
Answer: the signs of their original velocities reverse
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
mechanics, gravity
What is the gravitational attraction between two 400 pound sumo wrestlers standing 1 meter apart?
Answer: 0.0000022 N
Solver Input: Fg=?,m=400lb,M=400lb,r=1
Tutorial video:
Click here to see tutorial
mechanics, gravity
What is the gravitational force on a 400 pound sumo wrestler sky diving at a height of 15000 feet? The mass of the earth is 5.9742e+24 kg, and the radius of the earth is 6378.1 km.
Answer: 1775 N
Solver Input: Fg=?,m=400lb,h=15000ft,M=5.9742e24,r=6378.1km
Tutorial video:
Click here to see tutorial
mechanics, gravity
Satellites orbit the earth at a height of 38500 km. What is the speed of the orbiting satellite? The mass of the earth is 5.9742e+24 kg, the radius of the earth is 6378.1 km.
Answer: 2980 m/s
Solver Input: h=38500km,v=?,M=5.9742e24,r=6378.1km
Tutorial video:
Click here to see tutorial
mechanics, angular
Your CPU fan turns at 3000 rpm, and has a radius of 3 cm. How fast are the blades moving?
Answer: 9.42 m/s
Solver Input: w=3000rpm,r=3cm,v=?
Tutorial video:
Click here to see tutorial
mechanics, angular
It's getting hot. Your CPU fan increases its angular speed uniformly from 3000 to 4000 rpm in 1 second. How many turns did the fan make during this time?
Answer: 58 revolutions
Solver Input: wi=3000rpm,wf=4000rpm,t=1,theta_displaced=?rev
Tutorial video:
Click here to see tutorial
pendulum
A pendulum is 90 cm long. The speed of the bob is 150 cm/s as it passes through its lowest position. What is the maximum height the bob will rise to? At that height, what is the angle the pendulum makes with the vertical?
Answer: ymax = 0.11m, theta_max = 29 degrees
Solver Input: L=90cm,vmax=150cm/s,ymax=?,theta_max=?
Tutorial video:
Click here to see tutorial
pendulum
Question with absolute coordinates: a snapshot of a swinging 69 cm long pendulum reveals that it is at an angle of 15 degrees to the vertical. What are its x, y coordinates? What is the length of the arc it makes to the origin?
Question with relative coordinates: a swinging 69 cm long pendulum swings through 15 degrees. What horizontal and vertical distance did it swing through? What is the distance of the arc that it swung through?
Answer: dx = 0.179m, dy = 0.0235m, darc = 0.181m
Solver Input: L=69cm,dtheta=15,dx=?,dy=?,darc=?
Tutorial video:
Click here to see tutorial
pendulum
A pendulum swings at one Hertz. How long is the pendulum in centimeters?
Answer: 24.8 cm
Solver Input: f=1,L=?cm
Tutorial video:
Click here to see tutorial
springs
Using absolute coordinates: A spring has a spring constant of 2 N/m. It vibrates with an amplitude of 5cm. At x=3cm, what is its speed? At x=2cm, what is its speed?
Using initial/final coordinates: There's a mystery spring that's vibrating. I won't tell you anything about it except that at x=3cm, it has a speed of 5.657cm/s and at x= 2cm, it has a speed of 6.481cm/s. Now, tell me it's amplitude and spring constant!
Answer: at x=3, v=5.657cm/s. at x=2, v=6.481cm/s. A=5cm, k=2N/m
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
springs
A spring has a k = 2 N/m. You stretch it out to 5cm from its equilibrium then let go. What is its speed when it reaches its equilibrium position?
Answer: vmax = 7.071cm/s
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
gases
There are 300 mL of gas in your bowels. You decide to take an after-dinner bath, which raises your temperature from 37 C to 40 C. How many mL of gas do you have now?
Answer: 303 mL
Solver Input: Vi=300mL,Ti=37C,Vf=?mL,Tf=40C
Tutorial video:
Click here to see tutorial
gases
At rest, you have a body temperature of 37 C, and 300 mL of gas at a gauge pressure of 3.14 psi in your bowels. You decide to do some sit ups, which raise your body temperature to 38.5 C, and compress your gas to 250 mL. What is the gauge pressure now?
Answer: 6.8 psi
Solver Input: Ti=37C,Vi=300mL,P_gaugei=3.14psi,Tf=38.5C,Vf=250mL,P_gaugef=?psi
Tutorial video:
Click here to see tutorial
gases
You just purchased a 660 L tank of oxygen at 2000 psi stored at room temperature (20 C). The molecular weight of O2 is 32g/mol. How many mols of oxygen is in the cylinder? How many molecules of O2 is that? How many kg is that?
Answer: n=3734 mol, N=2.25e+27, m=119 kg
Solver Input: V=660L,P=2000psi,T=20C,M=32g/mol,n=?,N=?,m=?
Tutorial video:
Click here to see tutorial
gases
Oxygen has a density of 1.326 g/L at STP. What is oxygen's density on a hot summer's day when the temperature is 90 degrees Fahrenheit?
Answer: 1.27g/L
Solver Input: rhoi=1.326g/L,Ti=20C,Pi=1atm,rhof=?g/L,Tf=90F,Pf=1atm
Tutorial video:
Click here to see tutorial
buoyancy
The average human body has a density of 1.01 g/cm^3, and a weight of 178 pounds. What's the buoyant force of a person fully submerged in water? How about in the Dead Sea which has a density of 1.24 kg/L?
Answer: 176 poundforce in water, 218 poundforce in Dead Sea
Solver Input: rho_obj=1.01g/cm^3,Fw_obj=178poundforce,Fb=?poundforce,rho_fluid=1.24kg/L
Tutorial video:
Click here to see tutorial
buoyancy
You are interrogating Pinocchio in the Dead Sea. Pinocchio has a density of 1.01 g/cm^3. The Dead Sea has a density of 1.24 kg/L. What fraction of Pinocchio is floating above water?
Pinocchio's nose grows by 1/10 of his body size every time he lies. How many lies can he afford to tell?
Answer: Xa = 0.185
Solver Input: rho_obj=1.01g/cm^3,rho_fluid=1.24kg/L,Xa=?
Tutorial video:
Click here to see tutorial
hydrostatic
You are swimming at the 2m deep end of the pool when you dropped your locker key. If you dive to the bottom, how much pressure in psi pushes against your eardrums?
Your eardrum ruptures at 5 psi. How deep can you dive before the pressure reaches 5 psi?
At 5 psi, how much force pushes on your eardrum, which has an area of 0.55 cm^2?
Answer: At 2m, P=2.8psi. At 5 psi, h=3.5m. At 5 psi, F on your eardrum is 2N
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
bernoulli
See video for hydraulic press problem.
Answer: F2=45N, distance2=0.44mm
Solver Input: F2=?,F1=5,diameter2=9in,diameter1=3in,distance1=4mm,distance2=?mm
Tutorial video:
Click here to see tutorial
bernoulli, flow
A hose has a cross section area of 4 cm^2, and a flow rate of 150 mL/s. What is the speed of water travelling in the hose? At the end of the hose, someone's fingers squeeze the opening to an area of 1 cm^2. What is the speed of water shooting out of it?
Answer: v1=0.37m/s, v2=1.5m/s
Solver Input: A1=4cm^2,J=150mL/s,v1=?,A2=1cm^2,v2=?
Tutorial video:
Click here to see tutorial
bernoulli
A flushing toilet has a flow rate of 350 mL/s, and the stuff that flows through it has a density of 900 kg/m^3. The inlet has a diameter of 0.4 ft. The outlet is located 2m below. Long time no clean... it has an effective diameter of 0.2 ft. If the pressure at the inlet is 1.1 atm, what's the pressure at the outlet?
Answer: P2 = 1.27 atm
Solver Input: J=350mL/s,rho=900,diameter1=0.4ft,h1=2,P1=1.1atm,h2=0,diameter2=0.2ft,P2=?atm
Tutorial video:
Click here to see tutorial
heat
How much heat is needed to heat 10g of ice from 0 C to steam at 100 C? (hint: phase change involved)
How much heat is needed to heat 10g of water from 0 C to water at 100 C? (hint: NO phase change)
Answer: 30131 J if phase change, 4181 J if no phase change
Solver Input: dQ=?,m=10g,Ti=0C,Tf=100C
Tutorial video:
Click here to see tutorial
heat
20 kg of potion has a specific heat capacity of 0.8 cal/g/C, and is inside a calorimeter at a temperature of 95 C. Ron adds 5 kg of pure silver at 4 C to the potion to cool it off. If the calorimeter is negligible, what is the final temperature of the potion after the silver is added? Silver has a specific heat capacity of 0.235 J/g/K
Harry realized that the 18 kg pewter calorimeter has a specific heat capacity of 0.2 J/g/K. Based on this new information what is the final temperature?
Hermione realized that the potion will only work if it's cooled by pure silver to a final degrees of at least 90 C. How much silver does she need to add?
Answer: Tf=93.4 C if calorimeter ignored. Tf=93.5 C if calorimeter considered. 17.5kg needed to bring Tf to 90 C
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
heat
Object 1 has a mass of 123 grams, a specific heat capacity of 0.9 cal/g/C, and at an initial temperature of 40 C. Object 2 has a mass of 321 grams, a specific heat capacity of 0.3 cal/g/C, and at an initial temperature of 20 C. The two objects are brought together. What is the final temperature?
Object 3 comes in with a mass of 222 grams, a specific heat capacity of 1 cal/g/C, and at an initial temperature of 33 C. What is the final temperature of this new 3 object system?
Answer: 30.7 C for 2 object system. 31.9 C for 3 object system.
Solver Input: m1=123g,c1=0.9cal/g/C,Ti1=40C,m2=321g,c2=0.3cal/g/C,Ti2=20C,Tf=?C
Tutorial video:
Click here to see tutorial
heat
Hotel Jadis is made entirely of ice at 0 degrees Celsius. Walls, beds, toilets too...
The typical human urine is about 80 mL at 37 C. How much ice can your urine melt? Note: when you pee, some toilet will melt, some urine will freeze, and a final equilibrium temperature of 0 C is established.
In the real world, the urine probably won't freeze. If so, how much toilet will you melt?
It's a crime to destroy ice sculpture. All Jadis toilets are masterpieces made of 20kg of ice. How much urine are you allowed to pass?
Answer: frozen urine melts more ice. You are allowed to pass 43 L of urine.
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
optics, mirrors
A concave mirror has a focal length of 1m. What's the image's distance, and what does it look like, if the object is placed at 2.5, 2, 1.5, 1, 0.5 m in front of the mirror.
What about convex mirrors, and convex and concave lenses?
Answer: see tutorial video
Solver Input: f=1,i=?,o=2.5
Tutorial video:
Click here to see tutorial
optics, mirrors
A concave mirror has a radius of curvature of 140cm. How far must you stand in front of it in order to see an erect image of yourself magnified 3 times its original size?
Answer: o=46.7cm
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
optics, mirrors
An object is placed 1m in front of a mirror. The image is erect, and 1/3 the original size of the object. What is the radius of curvature of the mirror? What type of mirror is it?
Answer: r=-1m, it's a convex mirror
Solver Input: d_obj=1,erect_img,magnification=1/3,r=?
Tutorial video:
Click here to see tutorial
optics, lenses
A diverging lens has a focal length of 20cm. An object 10cm high is placed 20 cm in front of it. What is the height and distance of the image?
Answer: hi=-5cm, i=-10cm, negative bcz it's virtual
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
optics, lenses
A screen is placed 45cm behind a converging lens with a focal distance of 30cm. Where should the object be placed such that the image is cast onto the screen?
Answer: o=90cm
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
optics, lenses
I have an object, and I have a screen where the image will form. They are 50 cm apart. Now, I have a converging lens with a focal length of 10cm. Where should I place the lens such that the image will be cast on the screen?
Answer: place lens with o=36cm, i=14cm (o+i=50cm)
Solver Input: see tutorial video
Tutorial video:
Click here to see tutorial
electromag
Two electrons are 1 Angstrom apart. What is the repulsive force between them?
Answer: F = 2.3083086785009856e-8 N
Solver Input: q1=-1e,q2=-1e,r=1Angstrom,F=?
Tutorial video:
Click here to see tutorial
electromag
Two identical charges, separated by a distance of 1cm in water (dielectric constant = 80), experiences a repulsive force of 0.01 N. What is the magnitude of the charges?
Answer: q1 = 9.43438210181672e-8 C
Solver Input: r=1cm,K=80,F=0.01,q1=?,q2=?
Tutorial video:
Click here to see tutorial
electromag
An electron circles a proton at a radius of 0.5 Angstrom. What is the speed of orbit?
Answer: v = 2251217 m/s
Solver Input: q1=1e,q2=-1e,r=.5Angstrom,v=?
Tutorial video:
Click here to see tutorial
electromag
A proton starts off with a velocity of 14000 m/s and travels from one plate of a capacitor to the other. What is its final velocity if it goes from the (+) plate to the (-) plate? Note: the capacitor produces an electric field of 1 N/C over a distance of 1 m.
What about if it goes from the (-) plate to the (+) plate?
Answer: 19696 if along E, 2019 if against E
Solver Input: q=+e,vi=14000,vf=?,E=1,d=1
Tutorial video:
Click here to see tutorial
electromag
Ignoring relativity, what is the potential drop needed to accelerate an electron from rest to the speed of light (3e8 m/s)?
Answer: 255791
Solver Input: dV=?,q=-e,vi=0,vf=3e8
Tutorial video:
Click here to see tutorial
electromag
Charge one is +2 Coulombs, charge two is +3 Coulombs. They are 4 meters apart. How much work does it take to bring them together to 1 meter from each other?
Answer: 40446000000 J
Solver Input: q1=2,q2=3,ri=4,W=?,rf=1
Tutorial video:
Click here to see tutorial
electromag
Find the absolute potential experienced by X, 1 mile from a Coulomb of charge.
X can be anything: a test charge, or a real charge. It doesn't matter what's experiencing it. The absolute potential depends only on the charge that's producing it.
Answer: 5584883
Solver Input: V=?,d=1mi,q=1
Tutorial video:
Click here to see tutorial
electromag
A capacitor has a capacitance of 9e-8 Farad. The plates are 1 meter apart, and the dielectric in between them has a K = 82.67. What is the area of the plates?
Answer: 123 m^2
Solver Input: C=9e-8,d=1,K=82.67,A=?
Tutorial video:
Click here to see tutorial
electromag
A circuit has a voltage of 5 V, a resistance of 3 ohms. How long does it take for 1 Coulomb of charge to pass through a point in the circuit?
Answer: t = 0.6 s
Solver Input: V=5,R=3,t=?,q=1
Tutorial video:
Click here to see tutorial
electromag
Copper has a resistivity of 1.68e-8 ohm*m. A typical electronics wire has a cross section area of 1 mm^2. How long must this wire be in order to cause a resistance of 1 ohm?
Answer: L = 59.5 m
Solver Input: rho=1.68e-8,A=1mm^2,L=?,R=1
Tutorial video:
Click here to see tutorial
electromag
120 Coulomb of charge pass through a resistor every minute. The voltage across the resistor is 0.5 V. What's the power of the resistor?
Answer: P = 1 W
Solver Input: q=120,t=1min,V=.5,P=?
Tutorial video:
Click here to see tutorial
electromag
A line delivers 15 kW of power with a total resistance of 0.2 ohm. What voltage must the line be at in order to have an efficiency of 96%? At this voltage, what is the I2R power loss?
Answer: V = 268.32815729997475 V, I2R_loss = 625 W
Solver Input: P_delivered=15kW,R=.2,V=?,eff=.96,I2R_loss=?
Tutorial video:
Click here to see tutorial
electromag
A proton moves through a magnetic field of 3 Tesla at 4.7e5 m/s. If the angle between the velocity and the field is 30 degrees, what is the force on the proton?
Answer: F = 1.127986593019159e-13 N
Solver Input: q=e,B=3,v=4.7e5,theta_v_B=30,F=?
Tutorial video:
Click here to see tutorial
electromag
A magnetic field points into the page. Under its influence, an electron circles in the plane of the page with a speed of 3e5 m/s and at a radius of 3 Angstroms. Calculate the strength of the magnetic field.
Answer: B = 5684.254293120608 T
Solver Input: q=-e,v=3e5,r=3Angstrom,B=?
Tutorial video:
Click here to see tutorial
electromag
20cm wire experiences a force of 1 N inside a magnetic field of 1 Tesla. If the angle between the current (wire) and the field is 45 degrees, what must be the current in the wire?
Answer: I = 7.071067811865476 A
Solver Input: L=20cm,F=1,B=1,theta_I_B=45,I=?
Tutorial video:
Click here to see tutorial
electromag
A 50 coil rectangular loop with a width of 5cm and length of 8cm carries a current of 1 A, and is subjected to a magnetic field of 1 Tesla. If the angle of the area to the field is 10 degrees, what is the torque experienced by the loop?
Answer: tau = 0.0347 N*m
Solver Input: N=50,A=5*8cm^2,I=1,B=1,theta_A_B=10,tau=?
Tutorial video:
Click here to see tutorial
electromag
A railgun as shown, is subjected to a magnetic field of 0.2 Tesla, a resistance of 2 ohm, and a current of 2 A. The length of the projectile is 20cm, what is the speed of the projectile?
Answer: v = 100 m/s
Solver Input: B=.2,R=2,I=2,L=20cm,v=?
Tutorial video:
Click here to see tutorial
quantum
How much energy (in eV) does a photon of light with 450nm have?
Answer: E = 2.757082907783466 eV
Solver Input: E=?eV,lambda=450nm
Tutorial video:
Click here to see tutorial
quantum
The work function of a material is 3eV. What wavelength of light is needed to eject an electron from this material? What wavelength is needed to eject an electron with a velocity of 1e7 miles per hour?
Answer: 414 nm for ejection, 21 nm for 1e7 mi/h ejection
Solver Input: work_function=3eV,wavelength=?nm,v=1e7mi/h,m=1emass
Tutorial video:
Click here to see tutorial
quantum
What is the de Broglie wavelength of a 150 pound man running at 7 meters per second?
Answer: lambda = 1.3912218565116191e-36 m
Solver Input: lambda=?,m=150lb,v=7m/s
Tutorial video:
Click here to see tutorial
quantum
What is the energy of the helium n=1 state? How about n=2? How about n=infinity
Answer: -54eV at n=1, -13.6 at n=2, 0 at infinity
Solver Input: E=?eV,Z=2,n=1
Tutorial video:
Click here to see tutorial
quantum
What wavelength of light is released when an electron drops from n=2 to n=1 in a helium atom?
Answer: lambda = -30.45 nm
Solver Input: lambda=?nm,ni=2,nf=1,Z=2
Tutorial video:
Click here to see tutorial
quantum
What is the wavelength and energy of an emission from the Balmer series at n=5 for the hydrogen atom?
Answer: lambda = 434nm, E = 2.86eV
Solver Input: lambda=?nm,E=?eV,Balmer,n=5
Tutorial video:
Click here to see tutorial
mechanics, projectiles
A ball is thrown horizontally off a 100 feet cliff at 15 m/s. How far did the ball travel before hitting the ground?
Note: in the tutorial I accidentally put dy=100ft. However, dy=-100ft. Remember, up is positive, down is negative. Falling down a cliff makes dy negative. Luckily, the program was able to fix my mistake. However, you shouldn't rely on the program fixing your input mistakes, it doesn't always work.
Answer: dx = 37.4m
Solver Input: dy=-100ft,vix=15,dx=?ft
Tutorial video:
Click here to see tutorial