Question

47. At a particular moment, a student needs to stop his speedy bike to avoid a collision
with the barrier ahead at a distance 40 kms away from him. Immediately he shows
(retardation) the bike under braking at a rate of 8m/s2. If the bike is moving at a speed
of 24 m/s, when the brakes are applied would it stop before collision?
LE​

Answer 1

Answer:

If a car drives with a speed of 80 km/h and suddenly the driver reacts and pushes on the brakes with a reaction time of 0.6 seconds and the acceleration is -6.2 m/s^2 during the braking, how do I calculate the braking distance and the shutdown distance?

If a car drives with a speed of 80 km/h and suddenly the driver reacts and pushes on the brakes with a reaction time of 0.6 seconds and the acceleration is -6.2 m/s^2 during the braking, how do I calculate the braking distance and the shutdown distance?

Solution:

Given: speed( vo ) = 80 km/hr, reaction time = .6 sec, vf = 0, and deceleration = -6.2 m/sec 2

>>>Before you start check your values: 80 km/hr = 8000 m/3600 sec = 22.22 m/sec

Since there is a delay in stopping the car .6 sec the distance covered will be:

d = v x t

d = 22.22 x .6, ==> d = 13.332 m

As the breaks are applied::

v2f=v2o+2⋅a⋅d

0=22.222+2⋅−6.2⋅d

493.7284 = 12.4 x d, ==> d = 39.81680645 m

Total distance: 13.332 + 39.81680645 = 53.14880645 m or ≈ 53.15 m

Answer:

Total distance: 13.332 + 39.81680645 = 53.14880645 m or ≈ 53.15 m

Answer 2

Answer:

47. At a particular moment, a student needs to stop his speedy bike to avoid a collision

with the barrier ahead at a distance 40 kms away from him. Immediately he shows

(retardation) the bike under braking at a rate of 8m/s2. If the bike is moving at a speed

of 24 m/s, when the brakes are applied would it stop before collision?

LE