Given the relative success of Gradesaver last year, I thought it might be fun to do a what-happened-next document excerpt, for April Fool’s Day 2015.
Apologies to Ben. Thanks to Ding for the loan of a textbook. Thanks to ruth baulding for the suggestion, and to Kelly for the idea that skills in science – or lack thereof – might run in families.
Physics Assignment: Ben Kenobi
1: How long will it take a stone to hit the ground if it is dropped from the Council Spire? (height 54.6 m, acceleration due to gravity 9.8 m/s²)
How long it will take to hit the ground is irrelevant, as no rock has ever been or could ever be thrown from the Council Spire without the thrower suffering summary execution at the hands of the Council and so being unable to calculate any such thing.
2: An acceleration vector has a magnitude of 55 m/s² and an angle of 300°: what are its x and y components?
Its x component is the portion that runs at an angle of 0°, and its y component is the portion that runs at an angle of 90°.
3: What is the range of a cannon that launches its projectiles with an initial velocity of 350.0 m/s² at an angle of 35°?
The range of any projectile cannon is significantly less than that of an ion cannon, so nobody would ever actually use the cannon in question except for purposes of historical investigation. In which case, why does this question appear on a physics assignment?
4: Two persons are working together to remove a component of an engine. The stronger person attempts to unscrew the bolts holding the component, using a 12.3 cm wrench and a force of 612 Newtons. The weaker person can only apply 214 Newtons of force, but chooses a 41.1 cm wrench. Which person is likelier to succeed in unscrewing the bolts?
Obviously, the stronger person will appropriate the longer wrench from the weaker person, enabling him to apply a still greater torque. Therefore the stronger person is likelier to succeed.
5: Consider an object moving in a circle at a constant speed. If the centripetal force on the object were to suddenly double but the speed remained unchanged, what would happen to the radius of the circle in which it is traveling?
Since a radius is merely an imaginary construct to aid in understanding the properties of circles, nothing will happen to it, because nothing can happen to anything that does not exist.
6: What is the frequency of a sound wave whose wavelength is 1.0 m and whose amplitude is 150 dB? Assume that the air has a temperature of 15.0 °C.
One must hope that the frequency of this sound’s occurrence is very low indeed, as sounds whose intensities are in the 100-200 dB range can cause instantaneous deafness.
7: A metal emits electrons when illuminated with light. However, if the light wavelength is greater than 195 nm, no electrons are emitted. What is the work function of the metal?
The metal is not emitting electrons. Therefore it is neither working nor functioning. Therefore its work function is zero.
8: The index of refraction of water is 1.3. What is the speed of light in water?
The speed of light in water is how many units of distance per unit of time light can travel underwater, which is significantly greater than, for instance, the speed of Nasriel in water.
9: Give an example of a non-ceramic insulator.
10: Would a battery power a direct current circuit or an alternating current circuit?
This depends on whether the battery has any charge stored in it or not. If not, it will not power either circuit.
11: A person weighing 1000 Newtons is in a lift-tube car. What force is the lift-tube exerting on this person to cause an upward acceleration of 3.0 m/s²?
The lift-tube car is exerting so much force that it will doubtless soon break. The person should take the stairs, as this will serve the dual purpose of reducing some of the 1000 Newton weight, and saving resources by not destroying the lift-tube mechanism and inconveniencing others who may need to use it.
12: The hyperdrive of a ship of mass 100 metric tons is leaking coolant and the ship is without power. In the near vicinity are two planets, Sullust (gravity 9.8 m/s², atmospheric weight 10.1 N/cm²) and Korriban (gravity 8.2 m/s², atmospheric weight 12.3 N/cm²). Toward which planet should the pilot of the ship navigate in order to land safely, if a safe landing requires a gravity/atmospheric weight ratio of at most 2:3?
Toward Sullust. Korriban is reputedly a Sith planet and the pilot doesn’t want to run into one of those, not after what happened at Theed. A landing on Korriban could never be described as safe.
*All questions except for #12 are adapted from Exploring Creation with Physics: 2nd Edition, (2004) by Dr. Jay L. Wile, published by Apologia Educational Ministries, Inc. ISBN 978-1-932012-42-2.