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:
force F = 1.66 ×
N
Explanation:
given data
proton and an electron = 865 nm
solution
we get here force that is express as
force F = k q1 q2 ÷ r² ......................1
put here value and we get
force F = 9 ×
×
force F = 1.66 ×
N
Answer:
C. An ion with a +2 charge
Explanation:
I guess
Answer:
Second Choice.
Explanation:
Jack's Power = W/t
Jill's Power = 2W/(0.5)*t
2/0.5 = 4
Jill's Power = 4*W/t
Jill's Power is 4 times greater than Jack's
Second Choice
Answer:
Acceleration is percieved, not constant velocity.
Explanation:
You are most aware when the vehicle is accelerating. At constant velocity you would not be aware of the motion. Only if the system is accelerated the dynamics must be solved considering a pseudo-force (of inertial origin) acting.
It's because of this that:
(A) False. The acceleration can be detected from the inside of a closed car.
(B) False. You would be aware of the motion, but not because humans can sense speed but acceleration.
(C) False. Constant velocity cannot be felt in a closed car.
(D) False. Again, you can't feel constant speed.