Question

A block of mass 2.0 kg, starting from rest, is pushed with a constant force across a horizontal track. The position of the block as a function of time is recorded, and the data are shown in the table. What is the magnitude of the change in momentum of the block between zero and 4.0 seconds? 0.8 kg⋅m/s Answer A: 0.8 kilogram meter per second A 1.2 kg⋅m/s Answer B: 1.2 kilogram meters per second B 1.6 kg⋅m/s Answer C: 1.6 kilogram meters per second C 3.2 kg⋅m/s

Answer 1

The magnitude of the change in momentum of the block is 0.8 kg m/s.

Change in momentum

A change in momentum is the different between the final momentum and the initial momentum of the object.

The magnitude of the change in momentum of the block between zero and 4.0 seconds is calculated as follows;

$\Delta P = mv_f - mv_0\\\\\Delta P = m(v_f - v_0)$

where;

• Vf is the final velocity at 4 seconds = ?
• Vo is the initial velocity at 0 seconds = 0

From the graph the velocity at 4 seconds is calculated as;

$v_f = \frac{1.6 \ m}{4.0\ s} = 0.4 \ m/s$

ΔP = 2(0.4 - 0)

ΔP = 0.8 kg m/s

Thus, the magnitude of the change in momentum of the block is 0.8 kg m/s.

Learn more about change in momentum here: https://brainly.com/question/7538238

Answer 2

Answer: 1.6 kg*m/s

Explanation: There is change from 0m to 1.6m only.

Since the position at 0 seconds is 0m, and the position is 1.6 m at 4.0 seconds, the only change has to be 1.6m if the original position was 0.0m at 0.0seconds. It would be different if it was 1.0m at 0.5 seconds or something like that, but the change from 1.6 m to 0m is still 1.6m at 4 seconds.