Question

A 2956 kg car starts from rest at the top of a driveway of length 6 m that is sloped at 35◦ with the horizontal. An average frictional force of 3080 N impedes the motion. Find the speed of the car at the bottom of the driveway. The acceleration of gravity is 9.8 m/s 2 . Answer in units of m/s.

Answer 1

Answer:

7.41 m/s

Step-by-step explanation:

Force of a car inclined at an angle

F=mg Sin Θ where; m = 2956 kg , g = 9.8m/s² , Θ = 35⁰

F = 2956 x 9.8 x Sin 35 = 16615.82 N

Net force due to friction = 16615.82 - 3080 = 13535.82 N

To calculate acceleration; F= Ma

13535.82 = 2956 x a

a = 4.58 m/s²

From equation of motion

$V^{2} = V_{o} ^{2} + 2aS$

V² =  0 + (2 x 4.58 x 6)

V = $\sqrt{54.95}$

V = 7.41 m/s