A person driving a car with a speed 72 km/h suddenly sees a boy crossing the road. If the distance moved by car, before the person applies brakes is 5 m, the reaction time of the person is

When a situation demands our immediate action, it takes some time before we really respond. Reaction time is the time a person takes to observe, think and act. For example, if a person is driving and suddenly a boy appears on the road, then the time elapsed before he slams the brakes of the car is the reaction time. Reaction time depends on complexity of the situation and on an individual. You can measure your reaction time by a simple experiment. Take a ruler and ask your friend to drop it vertically through the gap between your thumb and forefinger . After you catch it, find the distance d travelled by the ruler. In a particular case, d was found to be 21.0 cm. Estimate reaction time.

If a person is driving a car at a speed of 30 m/s, then in how much time person will cover a distance of 1620 km?

A person crossing a road with a certain velocity due north, sees a car moving towards east.The relative velocity of the car w.r.t the person is sqrt2 times that of the velocity of the person.The angle made by the relative velocity with the east is

A person crossing a road with a certain velocity due north sees a car moving towards east The relative velocity of the car w.r.t the person is sqrt(2) times that fo the velocity of the persons. The angle made by the relative velocity with the east is

A person crossing a road with a certain velocity due north sees a car moving towards east The relative velocity of the car w.r.t the person is sqrt(2) times that fo the velocity of the persons. The angle made by the relative velocity with the east is

A car is moving with a constant accelaration of 4_(m//s^(2)) . On seeing a person infront of it the driver suddenly applies a brake . IF the car is moving with a velolcity of 20_(m//s) at the moment when driver sees the person and the reaction time of the driver is 2s, then the distance it travels after the movement it sees the person and the just before applying the break is

A person driving a car suddenly applies the brakes on seeing a child on the road ahead. If he is not wearing seat belt, he falls forward and hits his head against the steering wheel. Why

A driver is driving a car at a speed of 90km/h. he spots a child standing on his way and decided to apply the brakes but it took him 0.3s to actually apply the brakes. If the retardation produced by the brakes is 10m//s^(2) , calcualtion the total distance covered by car before coming to rest