1st Semester Exam (force, motion, energy, waves)

Velocity includes the speed that the object is moving and a

• direction

• time

• distance

• speed

Answer explanation

Velocity is defined as speed with a direction. Unlike speed, which is a scalar quantity, velocity is a vector quantity that includes both magnitude (speed) and direction. Therefore, the correct answer is 'direction'.

Complete the formula: speed = __/time

• distance

• mass

• direction

• temperature

Answer explanation

The formula for speed is derived from the relationship between distance, speed, and time. Speed equals distance divided by time, making 'distance' the correct choice to complete the formula.

Tags

NGSS.MS-PS3-1

If a person runs 100 meters in 10 seconds, what is their average speed

• 10 m/s

• 1 m/s

• 100 m/s

• 5 m/s

Answer explanation

To find average speed, divide distance by time. Here, 100 meters in 10 seconds gives an average speed of 100 m / 10 s = 10 m/s. Thus, the correct answer is 10 m/s.

Tags

NGSS.MS-PS3-1

The velocity of a plane is 500 miles per hour west. What is the speed of the plane

• 500 miles per hour west

• 500 miles per hour

• 500 miles per hour right

• 250 miles per hour

Answer explanation

The speed of the plane is the magnitude of its velocity. Since velocity includes direction, the speed is simply 500 miles per hour, regardless of the westward direction.

If a car travels 18,000 meters in 30 minutes, what is its average speed?

• 600 m/min

• 6 m/min

• 60 m/min

• 600 m/s

Answer explanation

To find the average speed, divide the distance by time. Here, 18,000 meters in 30 minutes equals 18,000 / 30 = 600 m/min. Thus, the correct answer is 600 m/min.

Tags

NGSS.MS-PS3-1

Acceleration is the rate of change of an object's:

• velocity

• speed

• force

• time

Answer explanation

Acceleration is defined as the rate of change of velocity, which measures how quickly an object's speed and direction change over time. Therefore, the correct answer is velocity.

What is the SI unit for finding speed?

• m/s

• m/s squared

• m

• s

Answer explanation

The SI unit for speed is meters per second (m/s), which measures the distance traveled in meters for each second of time. The other options do not represent speed: m/s squared is for acceleration, m is for distance, and s is for time.

The process of changing position is called:

• motion

• displacement

• reference point

• speed

Answer explanation

The process of changing position is known as motion. It refers to the movement of an object from one place to another, distinguishing it from terms like displacement, which measures the change in position.

The measure of the distance an object travels per unit of time is called:

• speed

• acceleration

• velocity

• motion

Answer explanation

The measure of the distance an object travels per unit of time is defined as speed. Unlike velocity, which includes direction, speed only considers how fast an object is moving.

Tags

NGSS.MS-PS3-1

What is the SI unit for measuring distance?

• meters

• kilometers

• seconds

• miles

Answer explanation

The SI unit for measuring distance is the meter. While kilometers, miles, and seconds are related to distance, only meters is the standard unit defined by the International System of Units (SI).