Answer:

Explanation:
GIVEN DATA:
Engine operating speed nf = 8325 rev/min
engine angular speed ni= 12125 rev/min
motorcycle angular speed N_m= - 4.2 rev/min
ratio of moment of inertia of engine to motorcycle is given as



The magnetic field strength in a coil is directly proportional to the number of turns, or loops, in the coil.
Therefore, when there are four loops instead of one, the magnetic field strength has increased four times, making it harder to push the magnet in.
Answer:
F = 120 N
Explanation:
Force x distance = energy
The bike has energy 1/2 . 80 . 6^2 = 1440 J
You are looking at an example of not reading the question properly.
Impulse = Force . time = change in momentum
F . 4 = 80 .6
F = 120 N
Answer:
a) 0.31 rad/s
b) 100 J
c) 6.67 W
Explanation:
(a) the force would generate a torque of:

According to Newton 2nd law, the angular acceleration would be

It starts from rest, then after 15s it would achieve a speed of

(b) The distance angle swept by it is:

Hence the work by the child

c) Average power to work per time unit

Answer: minimum speed of launch must be 7.45m/s
Explanation:
Given the following:
Height or distance (s) = 2.83m
The final velocity(Vf) at maximum height = 0
Upward motion, acceleration due to gravity(g) us negative = -9.8m/s^2
From the 3rd equation of motion:
V^2 = u^2 - 2gs
Where V = final velocity
u = initial velocity
Therefore, u = Vi
u = √Vf^2 - 2gs
u = √0^2 - 2(-9.8)(2.83)
u = √0 + 55.468
u = √55.468
u = 7.4476 m/s
u = 7.45m/s