physical laws questions

Use these questions to test your understanding. If you get them wrong, you will be linked back to the relevant part of the notes.

Be sure you study them thoroughly (don't just get a quick fix for your mistake) so your overall understanding is improved.

1. Scientists

a. work only to apply old theories to new observations

b. test theories against new observations

c. derive new theories without reference to observations

d. can solve any problem

e. do not accept observations that disagree with theory

2. Scientists

a. always progress steadily toward improved theories

b. tend to work within certain frameworks of thought that usually produce progress but occasionally are wrong

c. usually depend almost entirely on the writings of past authorities

d. get theories by studying concepts revealed in religious books and activities

e. work in ways that other people have no chance of understanding

3. Jupiter is about 5 times farther away from the sun than the earth is, and about 325 times more massive. Compare the gravitational forces holding the earth and Jupiter on their orbits.

a. there is not enough information to tell

b. the force on the earth is greater than that on Jupiter

c. the forces are equal

d. the force on Jupiter is 13 times greater than the one on the earth

e. the force on Jupiter is 325 times greater than the one on the earth

4. "Conservation of Energy" means that

a. Laws should be passed to preserve energy for future generations

b. The sum of the energy associated with motion (kinetic) and that associated with the ability to do work (potential) stays the same in a system

c. Energy can be converted into matter

d. An object in motion tends to retain the motion in the same direction and at the same speed.

e. Energy must be supplied to keep the planets moving in their orbits

5. Tides arise because

a. The gravity of the sun and moon distort the earth, and the distortion is larger for the water than the land

b. The gravity of the moon pulls the oceans outward

c. The gravity of the sun and moon cause the earth to move in a spiral pattern, setting up a large scale ocean wave movement

d. The gravities of the sun and moon do not exactly cancel, leaving a residual that pulls the oceans out of spherical shape

e. Friction between the ocean floors and the water interacts with tidal forces

6. When mass is annihilated

a. It disappears into another universe

b. It just disappears

c. It is converted into energy, as shown by E = mc²

d. It returns some time later

e. We don't know what happens, since we have never annihilated mass

7. When an object is about to fall and is high above the ground,

a. Its potential energy is at a maximum and its kinetic energy is at a minimum

b. Both its potential and kinetic energies are at a maximum

c. Both its potential and kinetic energies are at a minimum

d. Its potential energy is at a minimum and its kinetic energy is at a maximum

e. There is no fixed relation between its kinetic and potential energies

8. Which controls accelerate a car, according to Newton's Laws?

a. the accelerator

d. the steering wheel

e. all but the clutch

9. You live by the seashore on a planet with three moons in orbit around it. You will see

a. one high tide per day

b. two high tides per day

c. three high tides per day

d. a complicated pattern of tides depending on the relative locations of the moons

e. an unpredictable tide pattern

10. An object completely at rest may have some energy

a. because of its position relative to the earth

b. because of its kinetic energy

c. because energy is present everywhere

d. if it has no electrical charge

e. only if light is shining on it

11. An astronaut on the moon dropped a hammer and a feather from a height of 1.5 meters.

a. the hammer hit the surface first

b. the feather hit the surface first

c. they hit the surface at the same time

d. which hit first depends on the type of feather

e. which hit first cannot be predicted