Answer:
One positive and one negative
First figure shows the object position
Second shows the image position
Third shows the focal length.
Answer:
Magnetic field, B = 0.199 T
Explanation:
It is given that,
Radius of circular loop, r = 11.7 cm = 0.117 m
Magnetic flux through the loop, 
The magnetic flux linked through the loop is :


Here, 

or


B = 0.199 T
So, the strength of the magnetic field is 0.199 T. Hence, this is the required solution.
Answer:
616.223684211 N
Explanation:
= Resistive force on the wheel = 115 N
F = Force acting on sprocket
= Radius of sprocket = 4.75 cm
= Radius of wheel = 25 cm
Moment of inertia is given by

Torque

Torque is given by

The force on the chain is 616.223684211 N