Answer:
28.7%
Explanation:
efficiency = work output /work input × 100
A physical quantity is something which can be measured and whose measurement is necessary because all the laws of physics are given in terms of these physical quantities. The examples of physical quantity are mass, length, time, temperature, electric current, velocity , acceleration, force, work, weight,power, energy etc.
There are some quantities which cannot be measured and hence are not classified as physical quantities , for example, love, honesty, hatred etc
Thus a physical quantity is a quantity which can be measured.
A
The reason this is is because she the first sentence says that she believed that people would eat the mashed potatoes faster if they were brighter color.
That's efficiency. There's no law that it must be stated in percent.
The velocity of the tip of the second hand is 0.0158 m/s
Explanation:
First of all, we need to calculate the angular velocity of the second hand.
We know that the second hand completes one full circle in
T = 60 seconds
Therefore, its angular velocity is:

Now we can calculate the velocity of a point on the tip of the hand by using the formula

where
is the angular velocity
r = 15 cm = 0.15 m is the radius of the circle (the distance of the point from the centre of rotation)
Substituting,

Learn more about angular motion here:
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