Different speeds of light through two separate media ... and the difference in wavelength caused by the difference ... causes the bending of waves fronts associated with light rays.
AFTER the bend, since the light rays then travel in a different direction, we may also say that the 'velocity' has changed.
The body will take 20 seconds to cover a distance of 1000 m i.e. 1 km
His total displacement from his original position is -1 m
We know that total displacement of an object from a position x to a position x', d = final position - initial position.
d = x' - x
If we assume the lad's initial position in front of her house is x = 0 m. The lad then moves towards the positive x-axis, 5 m. He then ends up at x' = 5 m. He then finally goes back 6 m.
Since displacement = final position - initial position, and his displacement is d' = -6 m (since he moves in the negative x - direction or moves back) from his initial position of x' = 5 m.
His final position, x" after moving back 6 m is gotten from
x" - x' = -6 m
x" = -6 + x'
x" = -6 + 5
x" = -1 m
Thus, his total displacement from his original position is
d = final position - initial position
d = x" - x
d = -1 m - 0 m
d = -1 m
So, his total displacement from his original position is -1 m
Learn more about displacement here:
brainly.com/question/17587058
Answer:I need the ans to this one too
Explanation:
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
=
