Question

1. (sps8b) a baseball that is thrown in space will keep moving at a constant speed in a straight line until it hits something. (1 pt.)

a. newton’s 1st law
b. newton’s 2nd law
c. newton’s 3rd law

1. (sps8) which of the following statements are true of inertia? list the two that apply. (2 pts.)

a. inertia is a force.
b. inertia is a force which keeps stationary objects at rest and moving objects in motion at constant velocity.
c. all objects have inertia.
d. a more massive object has more inertia than a less massive object.

1. (sps8) a car accelerates at a rate of 3.0 m/s2 after stopping at a red light. if the mass of the car is 3000 kg, what force does its engine exert? (1 pt.)

a. 1000 n
b. 3000 n
c. 0.05 n
d. 9000 n

1. (sps8d) lucas pushes on a car stuck in a ditch with a force of 1000 n for 15 minutes. the car remains stuck. how much work did lucas do? (1 pt.)

a. 66.7 j
b. 0 j
c. 1.22 j
d. 22,000 j

1. (sps8d) which of the following is the best scientific definition of work? (1 pt.)

a. effort multiplied by distance
b. the conversion of energy from one form to another
c. a force being exerted over time
d. a force moving an object over a distance

1. (sps8d) many public buildings now have entrance ramps in addition to entrance stairs. which principle explains the idea behind entrance ramps? (1 pt.)

a. by increasing the distance, the force required decreases
b. by increasing the distance, the required force increases
c. by increasing the force, the required distance decreases
d. by increasing the force, the required distance increases

1. (sps8d) the sides of a sailboat slant sharply to help the boat move through the water. the boat itself acts as what type of simple machine? (1 pt.)

a. a wedge
b. a pulley
c. a screw
d. an inclined plane

Explanation:

Answer:

1. A. Newton's 1st Law
2. C. All objects have inertia. and D. A more massive object has more inertia than a less massive object.
3. D. 9000 N
4. B. 0 J
5. D. A force moving an object over a distance
6. A. By increasing the distance, the force required decreases
7. A. A wedge