Answer:
28.7%
Explanation:
efficiency = work output /work input × 100
Answer:
Object D
Explanation:
Use Newton's Second Law to determine the acceleration that each object has.
The force applied in both cases is 50 N, but the mass for object C and object D is different.
Let's start with object C first:
- F = ma
- 50 N = 10 kg · a
- 50 = 10a
- 5 = a
The acceleration object C undergoes is 5 m/s².
Now let's calculate object D next:
- F = ma
- 50 N = 2 kg * a
- 50 = 2a
- 25 = a
The acceleration object D undergoes is 25 m/s².
Object D has greater acceleration because it has a smaller mass. The object with a smaller mass will accelerate more in order to satisfy Newton's 2nd Law.
The channel is whatever was used to carry information from
one place to another, or from one person to another.
In this scenario, the channel is e-mail.
The work done to pull the sister back on the swing is equal to the increase in potential energy of the sister:

(1)
where m is the sister's mass, g is the gravitational acceleration and

is the increase in altitude of the sister with respect to its initial position.
By calling

the angle of the chain with respect to the vertical, the increase in altitude is given by

(2)
where L is the length of the chain.
Putting (2) inside (1), we find

from which we can find the mass of the sister: