Given data
efficiency (η) = 65 %
= 0.65
Machine provides (Work done by the machine) = 1300 × 50
= 65000 J
efficiency (η) = work done by the machine ÷ work supplied to the machine
0.65 = 65000 ÷ Input work
Input work = 100000 J
= 100 KJ
3 because opposites attract
Answer:
The period the field must be reduced to zero is 9.81 x 10⁻⁵ s
Explanation:
Given;
initial value of the magnetic field, B₁ = 0.276 T
number of turns of the solenoid, N = 517 turns
diameter of the solenoid, d = 10.5 cm = 0.105 m
induced emf, = 12.6 kV = 12,600 V
when the field becomes zero, then the final magnetic field value, B₂ = 0
The induced emf is given by Faraday's law;

Therefore, the period the field must be reduced to zero is 9.81 x 10⁻⁵ s
Answer:
1.04%
Explanation:
Given that,
The power of drill = 3.5 kW = 3500 W
Transferred kinetic energy = 5000 kJ during 15 seconds of use.
We need to find the percentage efficiency of the drill. It can be given by :

Where
Po and Pi are output and input powers.

So,

So, the percentage efficiency of the drill is 1.04%.
Answer:
Explanation:
Uranus takes about 84 years to circle the sun.
Pluto's existance has been known for 92 years. Uranius has completed 1 complete revolution. The numbers are reasonably close together and so Uranius is the answer.