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There are three long planks, each of len...

There are three long planks, each of length 5 meters. Three identical balls are placed on the planks as shown in the figure. Frictional force offered by planks I, II and Ill on the ball are `f_1, f_2` and `f_3` respectively.

If same force (push) is given to each ball then time taken to leave the planks I, II and III are 2 minutes, 1 minute and 4 minutes respectively. Which of the following options is correct regarding the friction force offered by the planks on the ball?

A

`f_1=f_2=f_3`

B

`f_1 gt f_2 = f_3`

C

`f_3 gt f_1 gt f_2`

D

`f_3 lt f_1 lt f_2`

Text Solution

Verified by Experts

The correct Answer is:
C
As the time taken to leave is greatest for III followed by I and II. So, the correct order will be `f_3 gt f_1 f_2`
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