Question

What is the acceleration of a 45 kg mass pushed with 15 N of force? What is the acceleration if the force changes to 25 N? What if the mass changes to 70 kg?

Answer 1

F = ma
Rearrange this so acceleration is the subject:
A = f/m

Now input your values into this equation for the first question :
A = f/m
A = 15/45
A = 0.33333333 m/s

Then using this same equation change the force of 15 to 25 :
A = f/m
A = 25/45
A = 0.55555556 m/s

For the last question keep the force of 15N but change the mass to 70kg into the same equation :
A = f/m
A = 15/70
A = 0.21 m/s (rounded)

Answer 2

Answer:

Part a)

$a = \frac{1}{3} m/s^2$

Part b)

$a = \frac{5}{9} m/s^2$

Part c)

$a = \frac{3}{14} m/s^2$

Explanation:

As per Newton's II law we know that

F = ma

Now we know that

m = 45 kg

F = 15 N

so we will have

$15 = 45 a$

$a = \frac{15}{45} = \frac{1}{3} m/s^2$

Now we have

m = 45 kg

F = 25 N

now again from Newton's Law

$25 = 45 a$

$a = \frac{25}{45} m/s^2$

$a = \frac{5}{9} m/s^2$

Now if mass is changed to 70 kg

again we have

$15 = 70 a$

$a = \frac{15}{70}$

$a = \frac{3}{14} m/s^2$