Ch 2-MGH practice quiz

A runner traveling at 5 m/s begins to acceleration at 1 m/s for 4 sec. without the acceleration, the runner would have ran only ___ m during 4 sec.: however, the acceleration added an extra ___m.

20 m 8 m

A car is traveling at a velocity of 40 m/s. the car then starts to accelerate at -5m/s^2. if the car accelerates for 6 sec., it loses ___m/s

30 m/s

The initial velocity of a car is 30m/s westwards. After some time, the car is traveling 45 m/s westwards During this interval, the car had a delta V= ______

45-30=15 m/s

A car travels 70 miles in 2 hr. During this trip, the car had an average speed of ___ miles per hour

70 / 2= 35 mph

Choose all the situations for which the abject is accelerating

A person rocking in a rocking chair A boomerang traveling at constant speed around in a circle

A car traveling in a straight line has a constant acceleration on 3 m/s squared. based on this infr. which of the following statements below is correct?

Every second the car will change its speed by 3m/s The car will change its speed by 1 m/s in a third of a second The car will change its velocity by 6 m/s after 2 sec.

A soccer player who has the ball is being chased by 4 other players from the opposing team. The player with the ball is running east at 20 m/s. Select the opposing player who has the same velocity as the player with the ball.

Numeber 03 who is running at 20 m/s in the eastward direction

Two sprinters will race around a track. which one will cross the finish line first?

The one with the greatest average speed

When driving a car in a straight line, in which situations do you obtain a nonzero acceleration?

When you release the gas pedal a little and the speedometer decreases When you press down father on the gas pedal and the speedometer increases

Rate of change of velocity rate of change of position rate of change of speed

acceleration Velocity none

Imagine you have taken a trip select all quantities about your trip that are rates

average acceleration during the trip hot dogs eaten per day coffees consumed per hour

acceptable units of speed

centimeters per day Inches per decade miles per hour

A car traveling eastwards gains 1 m/s eastwards every sec. the car is __

changing its speed speeding up accelerating changing its velocity

Which of the following quantities are vectors?

delta V Acceleration Velocity

The difference between instantaneous speed and instantaneous velocity is that instantaneous velocity also has a _____

direction

Cheetahs are the fastest mammals. Another way of phrasing this is to say that cheetahs can obtain the highest ___ speed of any mammal

instantaneous

A car starting from rest reaches 45 m/s in 5 sec. The car has an average acceleration of 9 m/___

second per second s squared s/s

Select all the cases for which the toy car will increase its intantaneous speed.

the velocity of the car is negative and the acceleration of the car is negative The velocity of the car is positive and the acceleration of the car is positive

A ___ is a quantity that must always be stated with magnitude and direction

vectors