Physics Quiz

What is the speed of an object at rest?

• 0.0 m/s

• 1.0 m/s

• 9.8 m/s

• 9.81 m/s

Answer explanation

An object at rest has no movement, which means its speed is 0.0 m/s. This is the definition of being at rest, confirming that the correct answer is 0.0 m/s.

Which of the following is the equation for acceleration?

Which of the following situations represents a negative displacement? (Assume positive position is measured vertically upward along a y-axis.)

• A cat stands on a tree limb.

• A cat jumps from the ground onto a tree limb.

• A cat jumps from a lower tree limb to a higher one.

• A cat jumps from a tree limb to the ground.

Answer explanation

Negative displacement occurs when an object moves downward. A cat jumping from a tree limb to the ground moves from a higher to a lower position, resulting in negative displacement.

Which of the following units is the SI unit of velocity?

• meter

• meter•second

• meter per second

• second per meter

Answer explanation

The SI unit of velocity is 'meter per second' (m/s), which indicates the distance traveled in meters for each second of time. The other options do not correctly represent the unit of velocity.

In the graph above, what is the correct description of any location to the left of the zero?

• negative displacement

• negative distance

• negative position

• negative change of displacement

Answer explanation

Any location to the left of zero on a number line represents a negative position. This indicates that the value is less than zero, which is why 'negative position' is the correct choice.

In the graph above, a toy car rolls from +3 m to +5 m. Which of the following statements is true?

Answer explanation

The initial position of the toy car is +3 m, which is represented as x_i. Therefore, the correct statement is x_i = +3 m. The other options are incorrect based on the given information.

Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of this graph describes what quantity?

• acceleration

• displacement

• instantaneous velocity

• position

Answer explanation

The slope of a tangent line on a position versus time graph represents the instantaneous velocity, as it indicates the rate of change of position at that specific moment in time.

Which of the following line segments on a position versus time graph is physically impossible?

• a horizontal line

• a straight line that slopes to the left

• a straight line that slopes to the right

• a vertical line

Answer explanation

A vertical line on a position versus time graph indicates an infinite speed, which is physically impossible. It suggests that an object is in two places at once, violating the laws of physics.

Tags

NGSS.MS-PS3-1

Acceleration is defined as

• a rate of displacement.

• the rate of change of displacement.

• the change in velocity.

• the rate of change of velocity.

Answer explanation

Acceleration is defined as the rate of change of velocity, meaning how quickly an object's velocity changes over time. This distinguishes it from displacement and velocity, making 'the rate of change of velocity' the correct choice.

Tags

NGSS.HS-PS2-1

Which of the following is the equation for average velocity?