Question

What is the net force and acceleration of a ball of mass 0.750 kilograms that is subjected to forces of 11.00 newtons and 7.00 newtons from opposite directions?

A.net force is 4.00 newton and the acceleration is 5.33 meters/sec
B.net force is 4.00 newton and the acceleration is 9.33 meters/sec
C.net force is 7.00 newton and the acceleration is 9.33 meters/sec
D.net force is 11.00 newton and the acceleration is 14.0 meters/sec

Answer 1

given mass  m = 0.75 kg
forces acting are aF1 = 11 N,in the +ve x direction and 
 F2 = -7 N , in the -ve x direction
net force is  vector sum of  F1,F2 = 11-7= 4 N
so acceleration is 
from Newton's second law  F = ma ==> a = F/m = 4/0.75 = 0.533 m/s2
so the answer is first option A
4N, 5.33 m/s2

Answer 2

Step-by-step explanation:

It is given that,

Mass of the ball, m = 0.75 kg

Force acting on the ball, F₁ = 11 N

Other force acting on the ball, F₂ = -7 N (opposite directions)

Let F is the net force acting on the ball. It can be calculated as :

$F=F_1+F_2$

$F=11-7$  

F = 4 N

Let a is the acceleration of the ball. Using second law of motion as :

$a=\dfrac{F}{m}$

$a=\dfrac{4\ N}{0.75\ kg}$

$a=5.33\ m/s^2$

So, the net force acting on the ball is 4 N and the acceleration of the ball is $5.33\ m/s^2$. Hence, the correct option is (a).