Answer: True
Explanation:
Because plants have an increase in vigar to grow
The component of weight(
mg) that is responsible for the motion of boxes on ramp is:
Where m = mass of the boxes.
g = Acceleration due to gravity = 9.8
= The angle the ramp makes with the ground. In this case it is 30°.
Since the frictional force is:
μ*N.
Where,
μ = Frictional Coefficient
N = Normal to the ramp =
Therefore, the frictional force becomes =
= μ*
Apply Newton's second law we would get:
- μ*
=
=>
=
μ
-- (A)
Now according to equation of motion:
Where x = 5.8m
= 0
= 0
= 10.24
Plug in the value in the above equation you would get:
= 1.1328
Plug in
in equation (A) and solve for
μ, you would get,
μ = 0.4439
if it is heat flow through a metal, it would be necessary to have a conductor so that the electrons can flow through it (delocalised electrons).
In terms of radiation, it would require a good absorber of heat (e.g. a black surface) so that the thermal energy flows through on the surface area.
Answer:
1)a. It is constant the whole time the ball is in free-fall.
2)b. = 14 m/s
3) e. = 19.6 m/s
Explanation:
1) given that the only force acting on the ball is gravity, gravity acts along the vertical axis. Since no other force acts on the ball then the horizontal velocity will remain constant all through the flight since there is no horizontal force acting on the ball.
2) speed = distance/time
horizontal distance = 56m
Time = 4 seconds
Speed = 56m/4s = 14m/s
3) acceleration due to gravity g = 9.8m/s^2
Initial vertical velocity = u
Final vertical velocity = v = -u
Using the law of motion;
v = u + at
a = acceleration = -g = -9.8m/s^2
t = time of flight = 4
Substituting the values;
-u = u - 4(9.8)
-2u = -4(9.8)
u = -4(9.8)/-2
u = 2(9.8) = 19.6 m/s
Initial vertical velocity = u = 19.6 m/s
Becuase of the earths gravitational pull you wont feel it because the earth is pulling you already and you arent big enough to feel the pull between the 2