Answer:
30°
Explanation:
The angle between the normal and the vertical is the same as the angle between the incline and the horizontal. We can show this with geometry.
The definition of velocity is a speed in a given direction. So the unit must include the speed and the direction that the object is moving. C. 31 m/s north is the correct answer, because the unit has the speed and the distance included. Although D has the same factors in it's answer, speed is only distance divided by time, and is not squared as it is shown incorrectly in answer D.
Answer:
0.52 N
Explanation:
k = 13 N/m
x = 0.04 m
Plug those values into Hooke's Law:
F = kx
F = (13 N/m)(0.04 m)
F = 0.52 N
Complete Question:
A basketball player tosses a basketball m=1kg straight up with an initial speed of v=7.5 m/s. He releases the ball at shoulder height h= 2.15m. Let gravitational potential energy be zero at ground level
a) Give the total mechanical energy of the ball E in terms of maximum height hn it reaches, the mass m, and the gravitational acceleration g.
b) What is the height, hn in meters?
Answer:
a) Energy = mghₙ
b) Height, hₙ = 5.02 m
Explanation:
a) Total energy in terms of maximum height
Let maximum height be hₙ
At maximum height, velocity, V=0
Total mechanical energy , E = mgh + 1/2 mV^2
Since V=0 at maximum height, the total energy in terms of maximum height becomes
Energy = mghₙ
b) Height, hₙ in meters
mghₙ = mgh + 1/2 mV^2
mghₙ = m(gh + 1/2 V^2)
Divide both sides by mg
hₙ = h + 0.5 (V^2)/g
h = 2.15m
g = 9.8 m/s^2
V = 7.5 m/s
hₙ = 2.15 + 0.5(7.5^2)/9.8
hₙ = 2.15 + 2.87
hₙ = 5.02 m
impulse = F × t
The greater the impulse exerted on something, the greater will be the change in momentum.
impulse = change in momentum
Ft = ∆(mv)