Question

part a - multiple choice
circle the best answer.

1. which of the following quantities includes both speed and direction?

a) buoyancy
b) velocity
c) time
d) distance

1. which graph shows constant acceleration?

a) straight, upward slope on a distance - time graph
b) flat line on a velocity - time graph
c) straight, upward slope on a velocity - time graph
d) curved line on a distance - time graph

1. which situation demonstrates newtons first law?

a) a ball rolling on grass slows down because of friction.
b) a rocket accelerates upward when gases push downward.
c) a student pushes a cart, and it speeds up.
d) a hammer strikes a nail, and the nail goes into the wood.

1. which has more inertia?

a) a marble
b) a soccer ball
c) a bowling ball
d) a tennis ball

Explanation:

1. Velocity is a vector quantity that includes both speed and direction. Buoyancy is an upward - acting force, time is a scalar quantity, and distance is also a scalar.
2. On a velocity - time graph, a straight, upward slope indicates a constant change in velocity over time, which means constant acceleration. A straight, upward slope on a distance - time graph represents constant velocity, a flat line on a velocity - time graph represents zero acceleration, and a curved line on a distance - time graph can represent non - constant velocity.
3. Newton's First Law states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. A ball rolling on grass slowing down due to friction is an example of an unbalanced force (friction) acting on a moving object. The other options are examples of Newton's Third Law (rocket) and Newton's Second Law (student pushing a cart, hammer striking a nail).
4. Inertia is related to mass. The more massive an object is, the more inertia it has. Among the options, a bowling ball has the largest mass, so it has the most inertia.

Answer:

1. b) Velocity
2. c) Straight, upward slope on a velocity - time graph
3. a) A ball rolling on grass slows down because of friction.
4. c) A bowling ball