Answer:
B = 1.353 x 10⁻³ T
Explanation:
The Magnetic field within a toroid is given by
B = μ₀ NI/2πr, where N is the number of turns of the wire, μ₀ is the permeability of free space, I is the current in each turn and r is the distance at which the magnetic field is to be determined from the center of the toroid.
To find r we need to add the inner radius and outer radius and divide the value by 2. Hence,
r = (a + b)/2, where a is the inner radius and b is the outer radius which can be found by adding the length of a square section to the inner radius.
b = 25.1 + 3 = 28.1 cm
a = 25.1 cm
r = (25.1 + 28.1)/2 = 26.6 cm = 0.266m
B = 4π x 10⁻⁷ x 600 x 3/2π x 0.266
B = 1.353 x 10⁻³ T
The strength of the magnetic field at the center of the square cross section is 1.3 x 10⁻³ T
Answer:
Just as it reaches the top of the bounce.
Explanation:
When an object reaches to the maximum height, its kinetic energy is equal to 0. It can be calculated as follows :
Where
m is mass and v is velocity
In this problem, Anita is bouncing a tennis ball on the sidewalk. She drops the ball and then watches it bounce back up.
It means, when it reaches the top of the bounce, Anita's tennis ball have zero kinetic energy. Hence, the correct option is (d).
Diagram A is the correct diagram
Answer: 90 m/s
Explanation:
For this situation we will use the following equations:
(1)
(2)
Where:
is the height of the model rocket at 4 s
is the initial velocity of the model rocket
is the velocity of the rocket at 4 s
is the time it takes to the model rocket to reach 200 m
is the constant acceleration due gravity and the rocket's thrust
Firstly, from equation (1) we have to find :
(3)
(4)
Now we have to substitute this value of in (2):
(5)
Finally:
This is the rocket's final velocity
