Answer:
1) 3.07kgm/s
2) 5.56kgm/s
3) 76.16N
4) 4.33kgm/s
5) 0.57s
6) -8.66J
Explanation:
Given
m = 0.221kg
v = 13.9m/s
θ = 25°
t = 0.073s
1) to get the magnitude of the initial momentum is the racquet ball. We use the formula,
P(i) = mv(i)
P(i) = 0.221 * 13.9
P(i) = 3.07kgm/s
2) Magnitude of the change in momentum of the ball,
P(i,x) = P(i) cos θ
P(i,x) = 3.07 * cos25
P(i,x) = 3.07 * 0.9063
P(i,x) = 2.78
ΔP = 2P(i,x)
ΔP = 2 * 2.78 = 5.56kgm/s
3) magnitude of the average force exerted by the wall,
F(ave) = ΔP/Δt
F(ave) = 5.56/0.073
F(ave) = 76.16N
4) ΔP(z) = mv(f) - mv(i)
ΔP(z) = 0.221*-7.8 - 0.221*11.8
ΔP(z) = -1.72 - 2.61
ΔP(z) = 4.33kgm/s
5) F(ave) = ΔP/Δt
Δt = ΔP/F(ave)
Δt = 4.33 / 76.16
Δt = 0.57s
6) KE(i) = 0.5mv(i)²
KE(f) = 0.5mv(f)²
ΔKE = 0.5m[v(f)² - v(i)²]
ΔKE = 0.5 * 0.221 [(-7.8)² - 11.8²]
ΔKE = 0.1105 ( 60.84 - 139.24 )
ΔKE = 0.1105 * -78.4
ΔKE = -8.66J
Answer:
The Light was reflected, b.
Explanation:
If the flashlight was pointed at the mirror, it was reflected because it did not stop on the mirror or go through the mirror or reflect in different ways.
1 block North and 2 blocks west are going to be legs of the triangle.
Total displacement is hypotenuse.
So, we can use Pithagorean Formula.
D² = 1² + 2² =5 m²
D =√5 m
question 3 is 3133333.33N/m^2 and question 4 is 4000000N^m2
