Question

Three cars (car F, car G, and car H) are moving with the same velocity when the driver suddenly slams on the brakes, locking the wheels. The most massive car is car F, the least massive is car H, and all three cars have identical tires.(a) Which car travels the longest distance to skid to a stop?(b) For which car does friction do the largest amount of work in stopping the car?

Answer 1

Part a)

all cars will travel equal distance before it stops

Part b)

Car F will have maximum work done by friction

Step-by-step explanation:

Part a)

As we know that the friction on Each car is given as

`F_f = \mu mg`

now the deceleration is given as

`a = -(F_f)/(m)`

`a = -\mu g`

so the deceleration is independent of the mass of the car

now the distance to stop the car is given as

`v_f^2 - v_i^2 = 2a d`

`0 - v^2 = -2(\mu g) d`

`d = (v^2)/(2\mu g)`

so all cars will travel equal distance before it stops

Part b)

Work done by friction force is given as

`W = F_f * d`

so we have

`W_f = \mu mg d`

so most massive car will have maximum work done done by friction

so Car F will have maximum work done by friction