Answer:
The correct option is (A).
Explanation:
When the temperature of the hot solid object increases then the radiation which emits from it gets shifted to smaller wavelength or higher frequencies. The hot appears red color.
The total energy emitted of a hot solid object is directly proportional to the fourth power of the temperature of the black body.
For example, when we switch on the light bulb, initially the radiation of the bulb appears dimmer. Then, it will become brighter. Then, it will turn yellow and then it becomes even white.
The color of the light emitted by a hot solid object depends on the temperature of the object.
Therefore, the correct option is (A).
Answer:
<em>The car will be moving at 5.48 m/s at the bottom of the hill</em>
Explanation:
<u>Principle of Conservation of Mechanical Energy</u>
In the absence of friction, the total mechanical energy is conserved. That means that
is constant, being U the potential energy and K the kinetic energy
U=mgh

When the car is at the top of the hill, its speed is 0, but its height h should be enough to produce the needed speed v down the hill.
The Kinetic energy is then, zero. When the car gets enough speed we assume it is achieved at ground level, so the potential energy runs out to zero but the Kinetic is at max. So the initial potential energy is transformed into kinetic energy.
We are given the initial potential energy U=45 J. It all is transformed to kinetic energy at the bottom of the hill, thus:

Multiplying by 2:

Dividing by m:

Taking square roots:



v = 5.48 m/s
The car will be moving at 5.48 m/s at the bottom of the hill
Answer: 324.135 kJ
Explanation:
Given
Mass of dropping is 
The initial height of dropping is 
The final height of dropping 
Gravitational potential energy is the function of height i.e.

Change in Gravitational Energy is
