PART A)
Here we know that
potential difference across the wire is
resistance of wire is
now by ohm's law
Part b)
Power rating is defined as rate of electrical energy
it is defined as
now we have
Answer:
The work done on the sled by friction, W = - 4593.75 J
Explanation:
Given data,
The combined mass of sled and the boy, m = 75 kg
The displacement of the boy, S = 25 m
The coefficient of the friction, u = 0.25
The frictional force acting on the boy,
<em>F = u η</em>
Where,
η - is the normal force acting on the boy (mg)
Substituting the values,
F = 0.25 x 75 x 9.8
= 183.75 N
Since the direction of the frictional force is against the direction of motion
F = - 183.75 N
The work done on the sled by friction,
W = F x S
= - 183.75 x 25
= - 4593.75 J
Hence, the work done on the sled by friction, W = - 4593.75 J
B. Earth's gravity has a stronger pull on the book when it is on earth than when it is in space.
When objects move farther away from the earth’s, the force of gravity on these objects gradually decline although their mass remains constant.
<h2>Answer:</h2>
<u>By changing the position of the fulcrum, the amount of effort Force also changes</u>
<h2>Explanation:</h2>
The mechanical advantage of a lever is changed when the distance between the pivot point (fulcrum) and the weight is changed. The way levers operate is by an effort applied at a point, which moves a load at another point through a balance point called the fulcrum. If the distance between the fulcrum and the effort is increased, the effort needed to lift a weight decreases proportionally.
