Wind farms, solar collectors, and nuclear power plants generate no pollution.
But wind farms make noise, wind and solar are both hazardous to birds, and there's no known means of disposing of nuclear plant waste that's completely safe.
Answer:
D. 12.4 m
Explanation:
Given that,
The initial velocity of the ball, u = 18 m/s
The angle at which the ball is projected, θ = 60°
The maximum height of the ball is given by the formula
h = u² sin²θ/2g m
Where,
g - acceleration due to gravity. (9.8 m/s)
Substituting the values in the above equation
h = 18² · sin²60 / 2 x 9.8
= 18² x 0.75 / 2 x 9.8
= 12.4 m
Hence, the maximum height of the ball attained, h = 12.4 m
The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object. As the force acting upon an object is increased, the acceleration of the object is increased. As the mass of an object is increased, the acceleration of the object is decreased.
For fundamental frequency of a string to occur, the length of the string has to be half the wavelength. That is,
1/2y = L, where L = length of the string, y = wavelength.
Therefore,
y = 2L = 2*0.75 =1.5 m
Additionally,
y = v/f Where v = wave speed, and f = ferquncy
Then,
v = y*f = 1.5*220 = 330 m/s
Answer:
The magnitude of change in momentum is (2mv).
Explanation:
The momentum of an object is given by the product of mass and velocity with which it is moving.
Let the mass of ball is m. A tennis player smashes a ball of mass m horizontally at a vertical wall. The ball rebounds at the same speed v with which it struck the wall.
Initial speed of the ball is v and final speed, when it rebounds, is (-v). The change in momentum is given by :
p = final momentum - initial momentum
So, the magnitude of change in momentum is (2mv).
