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.
D. Light as light is a wave
To Find: Diameter of soap bubble =? Solution: By Laplace's law of spherical membrane for a bubble. (Pi– Po) = 4T / r.
<span>A.
Gravitational force is proportional to the square of the distance
between the centers of both bodies.
FALSE:
Gravitational force is inversely proportional to the square of the distance between the centers of both bodies.
Which you can see from the formula: F = G * [m*M] /(d^2)
As you see in the equation, d^2 is in the denominator so the bigger d^2 (the square of the distance between the centers) of the objects the smaller the gravitational force.
B. The object with the smaller mass
does most of the moving because the object with the larger mass has too
much inertia to move any noticeable amount.
TRUE:
F = mass * acceleration => acceleration = F / mass => the larger the mass the smaller the acceleration.
C. Gravitational force is
proportional to the product of the two masses.
TRUE:
F = G [m*M] / (d^2)
The product of the two masses, m*M, is in the numerator, so F is proportional to this product.
D. Every object in the
universe that has mass attracts every other object in the universe that
has mass.
TRUE: that is a Universal Law discovered by Sir Isaac Newton.
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