That would be a the first law of newton's laws of motion because it stops from an external force
Answer:
A. potential energy is 258720 Joule
Explanation:
A.Gravitational potential energy is: PE = m × g × h
velocity = 15.33 m/s when the car reaches the bottom of the hill.
where, m = mass
g = acceleration due to gravity
h = height from the bottom of hill.
The potential energy is : m×g×h
=(2200×9.8×12)
=258720 Joule
B. at the bottom of the hill, the potential energy is converted into kinetic energy so PE at top = KE at bottom
kinetic energy=
(
)
where v = velocity
m= mass
therefore, v=
or, v=
or, v=15.33 m/s
Answer:
a. mechanical; require a medium to travel through
Explanation:
Longitudinal, transverse and surface waves are types of mechanical waves. For example, within the longitudinal waves are the sound waves, which needs a medium to propagate like the air. This is why sound does not travel in a vacuum.
And an example of a transverse wave is the waves that form in the water when a rock is thrown (ripples), these waves need a medium (the water) to propagate.
On the other hand, electromagnetic waves such as light waves do not need a medium to propagate, this is why we can see the light of distant stars because their light travels through the vacuum until it reaches us.
So, the answer is:
Transverse, surface, and longitudinal waves are all mechanical waves because they require a medium to travel through .
Answer:
0.488 m
Explanation:
If θ be the angle ladder makes with the plane
cos θ = 1.2 / 5
Tan θ = 4.04
Let the height a person of weight 600 N can climb be h from the ground .
Distance from the base point where ladder touches the floor = h / tanθ
= h / 4.04
Total reaction force = total downward force
R = 200 + 600
800 N
Frictional force = μ R
= .2 x 800
= 160 N
Taking moment of force about the point on the ladder where it touches the floor and balancing them
200 x 1.2 x .5 + 600 x h / tanθ = μ R x 1.2 / tanθ ( reaction at the top point of ladder where it touches the wall is R₁ and
R₁ =μ R )
= 200 x 1.2 x .5 + 600 x h / tanθ = 160 x 1.2 / tanθ
120 - 600 h / 4.04 = 47.52
120 - 47.52 = 600 h / 4.04
72.48= 148.51 h
h = 0.488 m
=