Answer:
The magnitude of the force on the wire is 2.68 N.
Explanation:
Given that,
Length of the wire, L = 5 m
Magnetic field, B = 0.37 T
Angle between wire and the magnetic field,
Current in the wire, I = 2.9 A
We need to find the magnitude of the force on the wire. The magnetic force in the wire is given by :
So, the magnitude of the force on the wire is 2.68 N. Hence, this is the required solution.
a) 2.75 s
The vertical position of the ball at time t is given by the equation
where
h = 4 m is the initial height of the ball
u = 12 m/s is the initial velocity of the ball (upward)
g = 9.8 m/s^2 is the acceleration of gravity (downward)
We can find the time t at which the ball reaches the ground by substituting y=0 into the equation:
This is a second-order equation. By solving it for t, we find:
t = -0.30 s
t = 2.75 s
The first solution is negative, so we discard it; the second solution, t = 2.75 s, is the one we are looking for.
b) -15.0 m/s (downward)
The final velocity of the ball can be calculated by using the equation:
where
u = 12 m/s is the initial (upward) velocity
g = 9.8 m/s^2 is the acceleration of gravity (downward)
t is the time
By subsisuting t = 2.75 s, we find the velocity of the ball as it reaches the ground:
And the negative sign means the direction is downward.