Answers:
B.) 
C.) 
Explanation:
The image attached shows the way the force
is acting on the block. Now, if we draw a free body diagram of the situation and write the equations for the Net Force in X and Y, we will have the following:
Net Force in X:
(1)
Where:
is the Normal force
is the magnitude of the force exerted on the block
is the angle
Net Force in Y:
(2)
Where:
is the Friction force (it is expresed with the
sign because this force may be up or down, we cannot know because the block is at rest)
is the gravity force
Rewrittin (1):
(3) This is according to option B
Rewritting (2):
(3) This is according to option C
Answer:
answer will be c: 1.5 seconds :)
Kinetic energy would increase sir.
Answer:
(4) weight
Explanation:
The centripetal force acting on the space shuttle in orbit is given by:

where
m is the mass of the shuttle
v is the tangential speed of the shuttle
r is the radius of its circular orbit
When the shuttle orbits the Earth, the centripetal force that keeps the shuttle in circular motion is given by the gravitational attraction between the shuttle and the Earth, which corresponds to the weight of the shuttle, and it is given by:

where
G is the gravitational constant
M is the Earth's mass
And this force, therefore, corresponds to the centripetal force.