Question

3. 2070 Supp (Set B) Q.No. 9 b The constant force resisting the motion of a car of mass 1500 kg is equal to one fifteenth of its weight if, when travelling at 48 km/h, the car is brought to rest in a distance of 50 m by applying the brakes, find the additional retarding force due to the brakes (assumed constant) and heat developed in the brakes. 14 Ans: 1666.67 N; 83333.5 J​

Answer 1

Answer:

V = 48km/hr

V = 40/3 = 13.33 m/s

v² - u² = 2as

0 - (40/3)² = 2 × a × 50

a = -16/9

|a| = 16/9 m/s

But a = 1/15(g) + additional acceleration

additional acceleration = 16/9 - 1/15(9.81)  

additional acceleration = 1.12377

f = ma

additional force = m × additional acceleration

additional force = 1500 × 1.12377

= 1685.667 kg.m/s²

__________________

Hope it helps you!!

:)