Answer:
A: The acceleration is 7.7 m/s up the inclined plane.
B: It will take the block 0.36 seconds to move 0.5 meters up along the inclined plane
Explanation:
Let us work with variables and set
As shown in the attached free body diagram, we choose our coordinates such that the x-axis is parallel to the inclined plane and the y-axis is perpendicular. We do this because it greatly simplifies our calculations.
Part A:
From the free body diagram we see that the total force along the x-axis is:
Now the force of friction is where is the normal force and from the diagram it is
Thus
Therefore,
Substituting the value for we get:
Now acceleration is simply
The negative sign indicates that the acceleration is directed up the incline.
Part B:
Which can be rearranged to solve for t:
Substitute the value of and and we get:
which is our answer.
Notice that in using the formula to calculate time we used the positive value of , because for this formula absolute value is needed.
Answer:
<h3>75m</h3>
Explanation:
If a cat walk 100m East, this means that it is walking in the positive x direction, the distance will therefore be +100m
If it turns around and walks 25 m west, the direction of movement is in the negative x direction i.e -25m
Taking the sum;
Displacement = +100m - 25m
Displacement of the cat = 75m
hence the cats displacement is 75m
False because when the training higher there is less oxygen
Answer:
D.diamond
Explanation:
Refraction occurs due to the bending of light rays as they pass from one medium to another. The light rays bend as their speed changes as they pass from one medium to another. The more the speed changes, the more the light bends and therefore more refraction occurs. When light passes from air to the diamond, the speed of light decreases more than any of the other materials listed in the given choices. So the light rays slow down the most diamond and so most refraction occurs in diamond.
Answer:
λ = 3.1824 10-25 m
Explanation:
To release the electron from the power well the absorbed photon electro must be greater than or equal to the energy of the electron in the power well
The photon energy is E_photon = 0.625 J
The speed of light is
c = λ f
Let's use Planck's equation
E = h f
We substitute
E = h c / λ
λ = h c / E
λ = 6.63 10-34 3 108 / 0.625
λ = 3.1824 10-25 m