Answer:f 30
Explanation: I am not really sure but try this
D.to bring light together
Answer:
The initial velocity of the ball is <u>39.2 m/s in the upward direction.</u>
Explanation:
Given:
Upward direction is positive. So, downward direction is negative.
Tota time the ball remains in air (t) = 8.0 s
Net displacement of the ball (S) = Final position - Initial position = 0 m
Acceleration of the ball is due to gravity. So,
(Acting down)
Now, let the initial velocity be 'u' m/s.
From Newton's equation of motion, we have:

Plug in the given values and solve for 'u'. This gives,

Therefore, the initial velocity of the ball is 39.2 m/s in the upward direction.
Answer:
The other end is called the south pole. When two magnets are brought together, the opposite poles will attract one another, but the like poles will repel one another. This is similar to electric charges.
Explanation:
The amount of metal in a closed cylindrical can that is 10 cm high and 4 cm in diameter if the metal on the top and the bottom is 0.1 cm thick and the metal on the sides is 0.05 cm thick is 8.8 cm.
The formula for calculating the volume of a cylinder is given below.
V = πr^2 h
Get the differential of the volume as shown:
dV = V/ h dh + V / r dr
V/ h = πr^2
V/ h = 2 πr h
Now, the differential becomes
dV = πr^2dh + 2πrh dr
Given the following parameters i.e. diameter and height
dh = 0.1 + 0.1 = 0.2 cm
dr = 0.05 cm
h = 10 cm
d = 4 cm
r = 2cm
Substituting the values in the above equation, we get
dV = 3.14(2)^2(0.2) + 2(3.14)(2)(10)(0.05)
dV = 2.512 + 6.28
dV = 8.792 cm
dV = 8.8 cm
If you need to learn more about diameter click here:
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