As per Newton's II law we know that

here we know that

so here we will have

so here if we need to increase the acceleration we need to increase the applied force while on increasing the mass or on increasing the friction force the acceleration will decrease.
So here correct answer will be
<em>A) force on the object.</em>
Answer:
The runner's acceleration was 
Explanation:
<u>Constant Acceleration Motion</u>
It's a type of motion in which the velocity of an object changes by an equal amount in every equal period of time.
Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, the following relation applies:

Solving for a:

The runner speeds up from vo=5 m/s to vf=9 m/s in t=4 seconds, thus:


The runner's acceleration was 
Answer:
2.67 m
Explanation:
k = Spring constant = 1.5 N/m
g = Acceleration due to gravity = 9.81 m/s²
l = Unstretched length
Frequency of SHM motion is given by

Frequency of pendulum is given by

Given in the question


The unstretched length of the spring is 2.67 m
I believe that the correct answer you are looking for is the distance traveled
Answer:
The metal atoms in the wire can't move, but their outer electrons can. The force pushes those electrons and they move to further parts of the wire, trying to reach the other end. As the electrons move away, new electrons flow into the wire through the battery to take their place.
Explanation: