Motion

What two things must you know to calculate speed?

• Mass and Time

• Mass and Distance

• Temperature and Mass

• Distance and Time

Answer explanation

Speed is calculated by dividing distance by time

Velocity is defined by speed in a specific location.

• True

• False

Answer explanation

velocity is found by knowing the direction of the object and the speed of the object.

What is the object or place used to decide if another object is in motion?

• Point of View

• Reference Point

• Motion Detector

• Acceleration

Answer explanation

Reference points are used to decide if other objects are in motion.

Kelly runs from 4:50pm until 5:20pm at an average speed of 7km/h. How far did she go?

Answer explanation

Calculate the time then convert the minutes to hours and then multiply by the speed to get the distance.

Velocity has no direction, but speed has a direction.

• True

• False

Answer explanation

Velocity has a direction but speed does not.

Momentum is a _______________quantity.

Answer explanation

it is a vector because it has magnitude and direction.

A runner has a momentum of 720 kg m/s and is traveling at a velocity of 5 m/s. What is his mass?

• 14.4kg

• 1400kg

• 144kg

• 360kg

Answer explanation

to calculate mass you must divide the momentum by the velocity

Mariah rides the escalator three floors up and then turns right to get to her favorite store in the mall.

Is an example of which of the following

• speed

• velocity

• acceleration

Answer explanation

this example is acceleration because they are going up and it tells the direction they are going.

A car travels 120 miles in 12 hours. What is the car's speed?

Answer explanation

to find the speed divide the distance by the time.

When a car goes around a corner at 20 mph, why do we say it accelerates

• The car is accelerating because of the velocity is constan

• The car accelerates because it's going 20 mph

• Cars always accelerate when they are in motion

• The car is accelerating because it's changing direction

Answer explanation

Acceleration is found with direction and speed.