Answer:
0.075 T
Explanation:
When a current-carrying wire is immersed in a region with magnetic field, the wire experiences a force, given by

where
I is the current in the wire
L is the length of the wire
B is the strength of the magnetic field
is the angle between the direction of I and B
In this problem we have:
L = 0.65 m is the length of the wire
I = 8.2 A is the current in the wire
F = 0.40 N is the force experienced by the wire
since the current is at right angle with the magnetic field
Solving the formula for B, we find the strength of the magnetic field:

A) 140 degrees
First of all, we need to find the angular velocity of the Ferris wheel. We know that its period is
T = 32 s
So the angular velocity is

Assuming the wheel is moving at constant angular velocity, we can now calculate the angular displacement with respect to the initial position:

and substituting t = 75 seconds, we find

In degrees, it is

So, the new position is 140 degrees from the initial position at the top.
B) 2.7 m/s
The tangential speed, v, of a point at the egde of the wheel is given by

where we have

r = d/2 = (27 m)/2=13.5 m is the radius of the wheel
Substituting into the equation, we find

Answer:
t = 1.58 s
Explanation:
given,
Speed of ranger, v = 56 km/h
v = 56 x 0.278 = 15.57 m/s
distance, d = 65 m
deceleration,a = 3 m/s²
reaction time = ?
using stopping distance formula


t is the reaction time

t = 1.58 s
hence, the reaction time of the ranger is equal to 1.58 s.
I think everything looks good but 2 might not be right, it might be B