Question

in the kinematics section of Your BOO
A force of 65 N changes the total momentum of a marble flying down an ultimate mini
ski jump (like the one at the back of the room) by 12 kg m/s. Determine the time
interval that the force acts on the ball. (3 marks)
F=65 N
mass = 12 kg·m/s
What is the time interval using a force of 65 N that changes the total momentum of a marble flying down an ultimate mini ski jump by 12kg-m/s?

Answer 1

Answer: To find the time interval that the force acts on the marble, we can use the impulse-momentum theorem, which states:

Impulse

=

Change in momentum

Impulse=Change in momentum

The impulse,

�

J, is calculated by multiplying the force,

�

F, by the time interval,

Δ

�

Δt, during which the force acts:

�

=

�

×

Δ

�

J=F×Δt

Given that the change in momentum (

Δ

�

Δp) is 12 kg·m/s and the force (

�

F) is 65 N, we can rearrange the formula to solve for

Δ

�

Δt:

Δ

�

=

Δ

�

�

Δt=

F

Δp

​

Plugging in the values, we get:

Δ

�

=

12

 

kg

⋅

m/s

65

 

N

Δt=

65N

12kg⋅m/s

​

Δ

�

=

12

65

 

s

Δt=

65

12

​

s

Δ

�

≈

0.1846

 

s

Δt≈0.1846s

So, the time interval that the force acts on the marble is approximately

0.1846

0.1846 seconds.

Explanation: