Before you start working on any motion problem, YOU decide which direction you're going to call 'positive'. Everybody almost always calls UP positive, and the acceleration of gravity points down, so it winds up negative. But you could just as well call DOWN the positive direction. Then, the cannonball is fired with a negative vertical speed, and the acceleration of gravity eventually robs all of its negative speed, and makes it start falling in the positive direction. The whole thing is your choice.
Answer:
The torque on the loop is
Nm
Explanation:
Given:
Current
A
Magnetic field
T
Area of loop

Angle between magnetic field and area vector
21°
Form the formula of torque in case of magnetic field,
г
Where
magnetic moment

г 
г 
г
Nm
Therefore, the torque on the loop is
Nm
Incomplete question.The complete question is attached below as screenshot along with figure
Answer:

Force is repulsive
Explanation:
Given data
Current I₁=5.00A
Current I₂=2.00A
Length L=1.20 m
Radius r=0.400m
To find
Force F
Solution
As the force is repulsive because currents are in opposite direction
From repulsive force we know that:

Substitute the given values
Answer: The 1 kg fragment will have three times the speed of the 3kg fragment.
Explanation:Here for the bomb, its chemical energy gets converted into the mechanical energy.
According to the law of conservation of momentum, the two bodies will have equal momentum and to satisfy this condition the lighter mass will have the higher velocity.
∵ momentum, p = mass × velocity
∴The 1 kg fragment will have three times the speed of the 3kg fragment.