Answer:
Variance is 25
Explanation:
Recall that the standard deviation is defined as the square root of the variance. therefore, if you know the standard deviation 
, square it and you get the variance:
Answer:
have tried it and the units end up being Nm^-2 (the unit of stress) however the unit for joules is Nm.
Source https://www.physicsforums.com/threads/why-does-1-2-stress-strain-equal-the-energy-stored-per-unit-volume-in-a-wire.565495/
Answer:
132 N
Explanation:
Given that a 1.1 kg hammer strikes a nail. Before the impact, the hammer is moving at 4.5 m/s; after the impact it is moving at 1.5 m/s in the opposite direction. If the hammer is in contact with the nail for 0.025 s, what is the magnitude of the average force exerted by the hammer on the nail
From Newton 2nd law of motion,
Change in momentum = impulse.
Change in momentum = m( V - U )
Substitute all the parameters into the formula
Change in momentum = 1.1 ( 4.5 - 1.5 )
Change in momentum = 1.1 × 3
Change in momentum = 3.3 kgm/s
Impulse = Ft
That is,
Ft = 3.3
Substitute time t into the formula above
F × 0.025 = 3.3
F = 3.3 / 0.025
F = 132 N
Therefore, the magnitude of the average force exerted by the hammer on the nail is 132 N.
Answer:
0.35 T
Explanation:
Side, a = 0.132 m, e = 27.1 mV = 0.0271 V, dA / dt = 0.0785 m^2 / s
Use the Faraday's law of electromagnetic induction
e = rate of change of magnetic flux
Let b be the strength of magnetic field.
e = dФ / dt
e = d ( B A) / dt
e = B x dA / dt
0.0271 = B x 0.0785
B = 0.35 T
An object's angular momentum is proportional to its moment of inertia.
Option D
<u>Explanation:</u>
Momentum is the measure of an object's movement with respect to its mass and velocity. So it is determined as the product of mass and velocity. An object moving in linear motion, will experience linear momentum.
Similarly, if an object moves in circular motion, then the momentum will be angular momentum. So it is measured as the product of moment of inertia with angular velocity.
Here L is the angular momentum , I is the moment of inertia and ω is the angular velocity.
Thus, the angular momentum is directly proportional to the moment of inertia.
