An electric motor is an electrical machine that converts electrical energy into mechanical energy.
Electric motors work on the principal of the interaction between magnetic field electr-magnetism. A loop which is carrying the current is placed in a magnetic field. The loop will experience a torque. The torque starts rotating the coil and the propellers start to rotate when the current passes through the loop.
Ok, assuming "mj" in the question is Megajoules MJ) you need a total amount of rotational kinetic energy in the fly wheel at the beginning of the trip that equals
(2.4e6 J/km)x(300 km)=7.2e8 J
The expression for rotational kinetic energy is
E = (1/2)Iω²
where I is the moment of inertia of the fly wheel and ω is the angular velocity.
So this comes down to finding the value of I that gives the required energy. We know the mass is 101kg. The formula for a solid cylinder's moment of inertia is
I = (1/2)mR²
We want (1/2)Iω² = 7.2e8 J and we know ω is limited to 470 revs/sec. However, ω must be in radians per second so multiply it by 2π to get
ω = 2953.1 rad/s
Now let's use this to solve the energy equation, E = (1/2)Iω², for I:
I = 2(7.2e8 J)/(2953.1 rad/s)² = 165.12 kg·m²
Now find the radius R,
165.12 kg·m² = (1/2)(101)R²,
√(2·165/101) = 1.807m
R = 1.807m
Answer:
The momentum of an object is defined as the mass of the object times the velocity of the object, as P = m*v.
So the equipment needed would be:
Something to measure the mass of the object, like a balance.
Something to measure the speed of the object, like a doppler radar, or a simpler thing may be a cronometer, with that you can measure the amount of time that the object needs to travel a given distance, and with that you can obtain the speed of the object.
Now you can notice that speed is different than velocity, this is true, velocity is a vector, so this has a direction, then you need something to fix the direction in which the object moves, in this way you can determine the velocity.
Answer:
A) The net force
Explanation:
If two forces of equal strength act on an object in opposite directions, the forces will cancel, resulting in a net force of zero and no movement.
Answer:
The applied torque is 3.84 N-m.
Explanation:
Given that,
Moment of inertia of the wheel is 
Initial speed of the wheel is 0 (at rest)
Final angular speed is 25 rad/s
Time, t = 13 s
The relation between moment of inertia and torque is given by :
So, the applied torque is 3.84 N-m.
