Question

7/21/22, 7:37 AMProblem Set ThreeNotes: Use 9.8 m/s 2 for the acceleration due to gravity. Formust be expressed in m/sLaw calculations, mass must be expressed in kg and velocity.A net force of 3500 N accelerates a car from rest to 46 km/h in 5s. What is the mass of the car?

Answer 1

Given:

The net force is F = 3500 N

The initial velocity of the car is

`v_i=0\text{ m/s}`

as the car starts from rest.

The final velocity of the car is

`\begin{gathered} v_f=\text{ 46 km/h} \\ =46*\frac{1000\text{ m}}{3600\text{ s}} \\ =12.78\text{ m/s} \end{gathered}`

The time duration is t = 5 s.

Required: The mass of the car.

Step-by-step explanation:

First, we need to calculate the acceleration of the car with the given information.

The acceleration can be calculated as

`\begin{gathered} a=(v_f-v_i)/(t) \\ =(12.78-0)/(5) \\ =2.56\text{ m/s}^2 \end{gathered}`

Using Newton's second law of motion, the mass can be calculated by the formula

`\begin{gathered} F=ma \\ m=(F)/(a) \end{gathered}`

On substituting the values, the mass of the car will be

`\begin{gathered} m=\frac{3500\text{ N}}{2.56\text{ m/s}^2} \\ =\text{ 1367.19 kg} \end{gathered}`

Final Answer: The mass of the car is 1367.19 kg.