Answer:

Explanation:
As we know that Beacon is rotating with angular speed

so we have



now we know that

here we will have


so we have


Answer: yes.
Explanation: The light that will be incidented on that metal is visible light.
It depends on 3 factors:
1. The temperature
2. The specific heat capacity of the metal
3. The thermal conductivity of the metal.
The metal getting warmer also depend on the reflection and the absorption of light energy in which it will surely absorb some energy and not reflect all.
When visible light is absorbed by an object, the object converts the short wavelength light into long wavelength heat. This causes the object to get warmer.
We use the kinematic equations,
(A)
(B)
Here, u is initial velocity, v is final velocity, a is acceleration and t is time.
Given,
,
and
.
Substituting these values in equation (B), we get
.
Therefore from equation (A),

Thus, the magnitude of the boat's final velocity is 10.84 m/s and the time taken by boat to travel the distance 280 m is 51.63 s
Answer : The correct option is, (d) 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.


where,
= specific heat of copper = 
= specific heat of water = 
= mass of copper = 120 g
= mass of water = 300 g
= final temperature of mixture = 
= initial temperature of copper = ?
= initial temperature of water =
Now put all the given values in the above formula, we get:


Therefore, the temperature of the kiln was, 