Answer:

Explanation:
Given data
length=100mm
Diameter=5mm
Thermal conductivity=5 W/m.K
Power=50 W
Temperature=25°C
The temperature of heater surface follows from the rate equation written as:

Where S can be estimated from the conduction shape factor for a vertical cylinder in semi infinite medium

Substitute the given values
![S=\frac{2\pi (0.1m)}{ln[\frac{4*0.1m}{0.005m} ]}\\ S=0.143m](https://tex.z-dn.net/?f=S%3D%5Cfrac%7B2%5Cpi%20%280.1m%29%7D%7Bln%5B%5Cfrac%7B4%2A0.1m%7D%7B0.005m%7D%20%5D%7D%5C%5C%20S%3D0.143m)
The temperature of heater is then:

The temperature reached by the heater when dissipating 50 W with the surface of the block at a temperature of 25°C.

Answer: The correct answer is "No".
Explanation:
Gravity: It is the force which causes object to fall on the earth. It is the force which attracts bodies towards each other.
Potential difference: It is defined as the potential acting between the two points. The work done in moving the unit positive charge from one location to the another location.
The potential difference in battery is caused by the electrodes. There are two terminals in battery: Negative terminal which is at lower potential and Positive terminal which is at higher potential. It forces the electrons to flow in the circuit which constitutes the current.
The gravity and the potential difference have no relation between them.
Therefore, gravity have no effect on the potential difference of a battery.
Answer: Released
Explanation: Energy is released in this reaction possibly in the form of heat thus it is an exergonic and or exothermic reaction.