Question

A 75.3 kg bobsled is pushed along a horizontal surface by two athletes. After the bobsled is pushed a distance of 8.1 m starting from rest, its speed is 7.1 m/s. Find the magnitude of the net force on the bobsled. Answer in units of N

Answer 1

233.43 N

Step-by-step explanation:

Force: This is the product of mass and acceleration of a body.

The formula for force is given as,

F = ma .............. Equation 1

Where F = Net force on the bobsled, m = mass of the bobsled, a = acceleration of the bobsled

We can look for a using the equation of motion

v² = u² + 2as.............. Equation 2

Where V = final velocity, u = initial velocity, a = acceleration, s = distance.

making a the subject of the equation,

a = (v²-u²)/2s................... Equation 3

Given: v = 7.1 m/s, u = 0 m/s ( from rest), s = 8.1 m.

Substitute into equation 3

a = (7.1²-0²)/(2×8.1)

a = 50.41/16.2

a = 3.1 m/s²

Also given: m = 75.3 kg

Substitute into equation 1

F = 75.3×3.1

F = 233.43 N

Hence the net force on the bobsled = 233.43 N