Physics- Chapter 4 Test Review

At which part (parts) of this graph of position versus time is the acceleration zero

• E only

• A, B and C only

• A only

• D and E only

• B and C only

Answer explanation

Only the linear segments A, B and C have zero acceleration.

Tags

NGSS.HS-PS2-1

At which part of this graph of position versus time is the acceleration positive?

• E

• A

• C

• D

• B

Answer explanation

A position versus time graph that has a positive slope which increases with time corresponds to a positive acceleration.The only segment where this happens is D.

Tags

NGSS.HS-PS2-1

You are driving a metric car that has a speedometer that displays in meters per second. When you look down at your speedometer, you see that it reads 19 m/s, then 7.3 s later you look down and it reads 35 m/s. What is your average acceleration over those 7.3 s?

• 16 m/s²

• 2.2 m/s²

• 2.6 m/s²

• 4.8 m/s²

• -2.2 m/s²

Answer explanation

a=Δv/Δt=(35−19) m/s divided by 7.3 s=2.19 m/s2

Tags

NGSS.HS-PS2-1

This velocity versus time graph shows the motion of a cart that a student moved by hand. In which time period—F, G, H, I, or J—was the acceleration the greatest?

• F (time 0 to 2 s)

• J (time 8 to 10 s)

• G (time 2 to 4 s)

• I (time 6 to 8 s)

• H (time 4 to 6 s)

Tags

NGSS.HS-PS2-1

Terra tosses a 0.30 kg volleyball straight up at 7.0 m/s. How high does it go?

• 0.0 m

• 1.4 m

• 2.5 m

• 1.5 m

• 0.71 m

Answer explanation

x=0 m+(7 m/s)(0.714 s)+.5(−9.8 m/s2)(0.714 s) squared =2.50 m

Tags

NGSS.HS-PS2-4

Two objects of similar shape, one weighing 10 N and the other weighing 20 N are dropped from the same height at the same time. Assuming that air resistance is negligible, which of the following statements is (are) true?

I. Both objects experience the same acceleration.

II. The heavier object reaches the ground first.

III. Both objects have the same speed just before hitting the ground.

• I only

• III only

• I and II only

• I, II and III

• I and III only

Tags

NGSS.HS-PS2-1

At which part (parts) of this velocity versus time graph is the acceleration negative?

• D

• E

• D and E

• B and D

• B

Answer explanation

The two parts of this graph where the acceleration is negative are B and D.

Tags

NGSS.HS-PS2-1

Jerry measures the time it took for a ball dropped from a balcony to hit the ground. His stopwatch reads 1.2 s. How high is the balcony?

• 12 m

• 14 m

• 7.1 m

• 5.9 m

• 7.3 m

Answer explanation

In this case, x_o = 0 m, v_o = 0 m/s, and x = h, the height of the balcony. Substitute these values into x = x_o + v_ot + ½at² to get h = ½gt² = ½(9.8 m/s²)(1.2 s)² = 7.06 m.

Tags

NGSS.HS-PS2-4

  If an object starts accelerating from rest at a rate of 28 m/s², then how far does it travel during the first second?

• 42 m

• 390 m

• 28 m

• 14 m

• 29 m

Answer explanation

Because the object starts at rest, v_o = 0 m/s. Plugging in this and t = 1 s into x = x_o + v_ot + ½at², we get that Δx = (0 m/s)(1 s) + ½(28 m/s²)(1 s)² = 14.0 m.

Tags

NGSS.HS-PS2-1

 A wagon, initially traveling at a constant 8.7 m/s, starts going down a hill that creates an acceleration of 1.4 m/s². What is the wagon's velocity 3.9 s after it starts accelerating down the hill?

• 8.7 m/s

• 34 m/s

• 11 m/s

• 14 m/s

• 5.5 m/s

Answer explanation

v = v₀ + at = 8.7 m/s + (1.4 m/s²)(3.9 s) = 14.2 m/s.

Tags

NGSS.HS-PS2-1