A block of mass m is placed on a smooth inclined wedge A B C of inclination θ as shown in the figure. The…

A block of mass m is placed on a smooth inclined wedge ABC of inclination θ as shown in the figure. The wedge is given an acceleration a towards the right. The relation between a and θ for the block to remain stationary on the wedge is
  1. a=gcosθ
  2. a=ssinθ
  3. a=gcosceθ
  4. a=gtanθ

Solution

In non-inertial frame of wedge 
Using pseudo force,
Free body diagram is given as



Normal reaction is balanced by mgcosθ

Where m is mass of the body, 

g is the acceleration due to gravity

a is the acceleration produced by external force..
macosθ=mgsinθ

a=gsinθcosθ
a=gtanθ

Asked in: NEET 2018

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