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A car whose total mass is 800kg travelling with a uniform velocity of 20m/s suddenly observes a stationary dog on it's path 50m ahead. If the total force applied on the breaking system on the car by the driver is 2000N what would most probably happen

1 Answer

4 votes

Answer:

Driver hits the dog

Step-by-step explanation:

From kinematics equation


v_f^(2)=v_i^(2)+2as and making a the subject


a=\frac {v_f^(2)-v_i^(2)}{2s}=\frac {0-20^(2)}{2*50}=-4m/s^(2)

F=ma=800*-4=-3200 N

The driver is required to apply a force of 3200 N to effectively not hit the dog. However, when the driver applies 2000 N, this is less the required force by 1200 N hence the driver hits the dog.

User Shishir Anshuman
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