Factors that affect heat transfer are:
1) Difference in temperature,
2) Mass of the object
3) Specific heat of the object
Hope this helps!
Answer:
F = 294.3 [N]
Explanation:
To solve this problem we must use Newton's second law which tells us that force is equal to the product of mass by acceleration. It is this particular case the acceleration is due to the gravitational acceleration since the body is in free fall.
Therefore we have:
F = m*g
where:
F = force [N]
m = mass = 30 [kg]
g = gravity acceleration = 9.81 [m/s^2]
F = 30*9.81
F = 294.3 [N]
The answer to your question is "A. a lower frequency of the siren.
Because the person in back of the ambulance will hear a lower frequency of the siren. This is because the waves are stretched out. A longer wavelength results in a lower frequency.
Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T
Resistivity, 
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :
r = 0.00199 m
or
The magnetic field on a current carrying wire is given by :
I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
Answer: Option (B) is the correct answer.
Explanation:
A process in which transfer of heat occurring when one object touches another object is known as conduction.
For example, when a pan is heated and then an egg is placed over the pan. Then there will be transfer of heat from pan towards the egg.
As a result, the egg gets cooked because the egg was touching the pan.
Hence, we can conclude that it is conduction because the egg is touching the pan.
