Acar of mass m, traveling at speed v, stops in time t when maximum braking force is applied. assuming the braking force is independent of mass, what time would be required to stop a car of mass 2m traveling at speed v?
a.â½tb. t√c. 2 td. 2t

option D

Explanation:

given,

mass of the car 1 = m

speed of car 1 = v

time taken to stop the car = t

mass of car 2 = m' = 2 m

speed of the car 2 = v

time taken by the car to stop = t' = ?

now,

we know,

F = m a....(1)

and force by the second car

F = m' a'

F = 2 m a'

from equation (1)

using equation of motion

v = u + at

0 = v - a t

again using equation of motion for the calculation of the time taken by the second car.

t' = 2 t

hence, the time taken by the second car is twice the time taken by the first car to stop.

The correct answer is option D

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).

inverse v=i*r

nice nice