A scooter starting from rest moves with a constant acceleration for a time _1, then with a constant velocity for the next _2, and finally with a constant deceleration for the next _3 to come to rest. A 500N man sitting on the scooter behind the driver manages to stay at rest with respect to the scooter without touching any other part. The force exerted by the seat on the man is:

D. > 500N for time _1 and _3 and 500N for _2.

A scooter starting from rest moves with a constant acceleration f…

MCQ

A scooter starting from rest moves with a constant acceleration for a time $\triangle\text{t}_1,$ then with a constant velocity for the next $\triangle\text{t}_2,$ and finally with a constant deceleration for the next $\triangle\text{t}_3$ to come to rest. A $500N$ man sitting on the scooter behind the driver manages to stay at rest with respect to the scooter without touching any other part. The force exerted by the seat on the man is:

A
$500N$ throughout the journey.
B
Less than $500N$ throughout the journey.
C
More than $500N$ throughout the journey.
✓
$> 500N$ for time $\triangle\text{t}_1$ and $\triangle\text{t}_3$ and 500N for $\triangle\text{t}_2.$

✓

Answer

Correct option: D.

$> 500N$ for time $\triangle\text{t}_1$ and $\triangle\text{t}_3$ and 500N for $\triangle\text{t}_2.$

During the time interval $\triangle\text{t}_2,$ the scooter is moving with a constant velocity, which implies that the force exerted by the seat on the man is $500N ($for balancing the weight of the man$).$
During the time interval $\triangle\text{t}_1$ and $\triangle\text{t}_3,$ the scooter is moving with constant acceleration and deceleration, which implies that a frictional force is also applied.
Therefore, the net force exerted by the seat on the man should be $> 500N.$