Answer:
A kilowatt (kW) is a unit of power.
Explanation:
The power of an object is given by :

Here,
E is the energy required
t is time
The SI unit of power is Watts and the SI unit of energy is Joule. the commercial unit of energy is kilowatt per hour.
Option (1) : A kilojoule (kJ) is a unit of power is incorrect.
Option (2) : A gigawatt (GW) is a unit of energy is incorrect.
Option (3) : A watt (W) is a unit of energy is incorrect.
Option (4) : A kilowatt x hour per year (kWh/yr) is a unit of energy is incorrect.
Option (4) : A kilowatt (kW) is a unit of power is correct.
Hence, the correct option is (d).
Answer:
Torque,
Explanation:
Given that,
The loop is positioned at an angle of 30 degrees.
Current in the loop, I = 0.5 A
The magnitude of the magnetic field is 0.300 T, B = 0.3 T
We need to find the net torque about the vertical axis of the current loop due to the interaction of the current with the magnetic field. We know that the torque is given by :

Let us assume that, 
is the angle between normal and the magnetic field, 
Torque is given by :

So, the net torque about the vertical axis is
. Hence, this is the required solution.
Answer:
Explanation:
The moment of inertia is the integral of the product of the squared distance by the mass differential. Is the mass equivalent in the rotational motion
a) True. When the moment of inertia is increased, more force is needed to reach acceleration, so it is more difficult to change the angular velocity that depends proportionally on the acceleration
b) True. The moment of inertia is part of the kinetic energy, which is composed of a linear and an angular part. Therefore, when applying the energy conservation theorem, the potential energy is transformed into kinetic energy, the rotational part increases with the moment of inertia, so there is less energy left for the linear part and consequently it falls slower
c) True. The moment of inertial proportional to the angular acceleration, when the acceleration decreases as well. Therefore, a smaller force can achieve the value of acceleration and the change in angular velocity. Consequently, less force is needed is easier
Answer:
The ball has an acceleration of -380 m/s², this means the ball slows down
An acceleration of -380 m/s² is the equivalent of 38.736 g's
Explanation:
Step 1: Data given
Velocity of the baseball at time t=0 = 38 m/s
At time t, the ball stops. This means v = 0
time before stops = 0.1s
Step 2: Calculate the acceleration
v= v0+at
with v= the velocity of the ball at time t = 0. v= 0
with v0 = the velocity of the ball at time t=0. v0 = 38 m/s
with a= the acceleration in m/s²
with t = time in seconds
0 = 38 + a*0.1
a = -380 m/s²
The ball has an acceleration of -380 m/s², this means the ball slows down
An acceleration of -380 m/s² is the equivalent of 38.736 g's