Question

A 9230-kg truck collides head on with a 1250-kg parked car. The vehicles entangle together and slide a linear distance of 10.6 meters before coming to rest. Assuming a uniform coefficient of friction of 0.820 between the road surface and the vehicles, determine the pre-collision speed of the truck.

Answer 1

To determine the pre-collision speed of the truck, use the principles of conservation of momentum and the equation for final velocity. Calculate the total mass of the entangled vehicles, and use the given information and formulas to find the initial velocity of the truck.

Step-by-step explanation:

To determine the pre-collision speed of the truck, we can use the principles of conservation of momentum.

1. First, calculate the total mass of the entangled vehicles by adding the mass of the truck (9230 kg) and the car (1250 kg).
2. Next, calculate the final velocity of the vehicles using the formula for conservation of momentum: final velocity = (mass of truck * initial velocity of truck + mass of car * initial velocity of car) / total mass of entangled vehicles.
3. Since the truck comes to rest after the collision, the final velocity of the entangled vehicles is 0 m/s. Rearrange the formula to solve for the initial velocity of the truck: initial velocity of truck = -(mass of car * initial velocity of car) / mass of truck.
4. Lastly, substitute the given values to calculate the pre-collision speed of the truck.

Answer 2

=>By the work energy relation:-

=>W = ∆KE

=>Ff.s = 1/2(M+m)v^2

=>µk x N x s = 1/2(M+m)v^2

=>µk x (M+m) x g x s = 1/2(M+m)v^2

=>v = √[2µkgs]

=>v = √[2 x 0.82 x 9.8 x 10.6]

=>v = 13.05 m/s

By the law of momentum conservation:-

=>Mu = (M+m)v

=>9230u = (9230+1250) x 13.05

=>u = 14.82 m/s

Step-by-step explanation: