The first one it's very windy today and will rain later.
Answer:
4.55 minute
Explanation:
51 km = 51000 m
the ray of light travels due east 51000 m , bounces back from reflecting mirrors . The reflected light gets focused on a point 135 m south . Let the angle between incident light and reflected light be θ.
tanθ = 135 / 51000
θ = .1516 degree
= .1516 x 60 minute
= 9.09 minute
angle between incident ray ( east - west ) and normal = 9.09 / 2
= 4.55 minute Ans
So there are different ways this could be solved. I'll do try to explain it the way I was taught...
Simon is riding his bike at 12 km/hr relative to the sidewalk, away from where Keesha is.
Simon throws the ball at Keesha, at 5 km/hr.
Keesha sees the ball approaching her at (12-5) = 7 km/hr relative to the ground to her.
Therefore the answer is: 7 km/hr
Answer:
Wt= 0.73kJ, Wg=0.21kJ Wn= 0J
(B) Wf= 0.096kJ
Explanation:
See attachment below.
