<span>B) 0.6 N
I suspect you have a minor error in your question. Claiming a coefficient of static friction of 0.30N is nonsensical. Putting the Newton there is incorrect. The figure of 0.25 for the coefficient of kinetic friction looks OK. So with that correction in mind, let's solve the problem.
The coefficient of static friction is the multiplier to apply to the normal force in order to start the object moving. And the coefficient of kinetic friction (which is usually smaller than the coefficient of static friction) is the multiplied to the normal force in order to keep the object moving. You've been given a normal force of 2N, so you need to multiply the coefficient of static friction by that in order to get the amount of force it takes to start the shoe moving. So:
0.30 * 2N = 0.6N
And if you look at your options, you'll see that option "B" matches exactly.</span>
Answer:
Explanation:
We shall apply Stefan's formula
E = AσT⁴
When T = 300
I₁ = Aσ x 300⁴
When T = 400K
I₂ = Aσ x 400⁴
I₂ / I₁ = 400⁴ / 300⁴
= 256 / 81
= 3.16
I₂ = 3.16 I₁ .
Answer:
The extension of the second wire is 
Explanation:
From the question we are told that
The length of the wire is 
The elongation of the wire is 
The tension is 
The length of the second wire is 
Generally the Young's modulus(Y) of this material is
Where 
Where A is the area which is evaluated as
and 
So
Since the wire are of the same material Young's modulus(Y) is constant
So we have
Now the ration between the first and the second wire is
Since tension , radius are constant
We have
substituting values
Answer:
Explanation:
When the pendulum falls freely the net acceleration due to gravity is zero.
As we know that the time period of simple pendulum is inversely proportional to the square root of acceleration due to gravity, thus the time period becomes infinity.
