For years, space travel was believed to be impossible because there was nothing there Rockets could push off in space in order t
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The question is missing the diagram. Also, the choices must have pictorial representation. So, I have attached the missing diagram and the pictorial representation of the vectors.
Answer:
The correct representation is attached below. Force and acceleration will be towards the center of rotation while the velocity will be along the tangent to the circular motion. <u>Option (D).</u>
Explanation:
From the figure, we can conclude the following points:
1. The cylinder is under a uniform circular motion as the circular table is moving at constant speed.
2. For a circular motion, velocity acts along the tangent to the circular path.
3. For a circular motion, centripetal force acts on the body that causes it move around a circular path.
4 The direction of the centripetal force is radially inward towards the center of rotation.
5. The centripetal force causes a centripetal acceleration acting on the body.
6. From Newton's second law, the net acceleration of a body is in the same direction as that of the net force acting on it. So, centripetal acceleration also acts in the radially inward direction.
Therefore, from the above conclusions, it is clear that velocity will act in the horizontal direction at the given instance of time and force and acceleration will act vertically down for the given instance.
This is shown in the picture below. The option (D).
Answer:
The second snowball hits the ground with a kinetic energy of 100 Joules
Explanation:
Given that,
From the edge of a roof you throw a snowball downward that strikes the ground with 100 J of kinetic energy. It is a case of conservation of energy.
At the highest point,
At lowest point,
From above two equation, we get :
Kinetic energy, K = 100 J
So, the second snowball hits the ground with a kinetic energy of 100 Joules. So, the correct option is (A).
Answer:
5.7 m
Explanation:
AD = length of the ladder = L = 8 m
AB = distance of the center of mass of the ladder = (0.5) L = (0.5) 8 = 4 m
AC = distance of person on the ladder from the bottom end = x
W = weight of the ladder = 240 N
= weight of the person = 710 N
F = force by the wall on the ladder
N = normal force by ground on the ladder = ?
Using equilibrium of force along the vertical direction
N = + W
N = 710 + 240
N = 950 N
μ = Coefficient of static friction = 0.55
f =static frictional force on the ladder
Static frictional force is given as
f = μ N
f = (0.55) (950)
f = 522.5 N
Force equation along the horizontal direction is given as
F = f
F = 522.5 N
using equilibrium of torque about point A
F Sin50 (AD) = W Cos50 (AB) + ( Cos50 (AC))
(522.5) Sin50 (8) = (240) Cos50 (4) + (710) Cos50 (x)
x = 5.7 m
Answer:
Part a)
Part b)
Part c)
Explanation:
Part a)
As we know that the velocity of the tip of the kicker's shoe is given as
also the length of the tip of the shoe from his hip joint is given as
now the angular speed is given as
Part b)
As we know that force on the ball is given as rate of change in momentum of the ball
so it is given as
so we have
Part c)
As we know that the formula of range is given as
now for maximum range we know