Period = 2 seconds.
frequency = 1/2 cycle/second = 1/2 Hz
If it falls twice every four seconds, then it falls once every two seconds, therefore one falling period is two seconds.
Hz is equal to cycles per second. So if it goes through one cycle per two seconds, then it goes through 1/2 cycle per one second.
Hope this helps!
Answer:
Correct answer: 11. Total distance d = 200m ; 12. Vav = 3.63m/s ;
13. Total displacement Dt = 0m ; 14. V₂(10s-15s) = 0 m/s ;
15. V₃(15s-40s) = 4 m/s ; 16. V₁(0s-10s) = 6 m/s > V₄(40s-55s) = 2.67 m/s
Explanation:
The whole movement can be divided into four stages.
In the first stage the subject moves 60m in a positive direction for 10s,
in the other it is stationary for 5s, in the third it moves 100m in the opposite (negative) direction for 25s and in the fourth in the positive 40m for 15s.
11. Total distance = 60 + 0 + 100 + 40 = 200m
12. The formula for calculating the average speed (velocity) is
Vav = (S₁ + S₂ + S₃ + S₄) / (t₁ + t₂ + t₃ + t₄)
Vav = (60 + 0 + 100 + 40)/ (10 + 5 + 25 + 15) = 200/55 = 3.63 m/s
13. The movement started from the origin and ended at the origin
Total displacement is zero meters.
14. The speed between 10s and 15s is zero, because he did not move.
15. V₃ = S₃/t₃ = 100/25 = 4 m/s
16. V₁ = S₁/t₁ = 60/10 = 6 m/s and V₄ = S₄/t₄ = 40/15 = 2.67 m/s
V₁ > V₄
God is with you!!!
Answer:
2.7 m/s
Explanation:
Draw a free body diagram of the ball. There are two forces:
Weight force mg pulling down
Tension force T pulling 39° above the horizontal
Sum of the forces in the y direction:
∑F = ma
T sin θ − mg = 0
T = mg / sin θ
Sum of the forces in the radial (+x) direction:
∑F = ma
T cos θ = m v² / r
Substitute:
(mg / sin θ) cos θ = m v² / r
mg / tan θ = m v² / r
g / tan θ = v² / r
v = √(gr / tan θ)
Given that r = 0.6 m and θ = 39°:
v = √(9.8 m/s² × 0.6 m / tan 39°)
v ≈ 2.7 m/s
Answer:
Explanation:
Given that,
g = 31 ft/s²
For every 1 lbf force, the compression is 1in
Then we can know the spring constant.
From Hooke's Law
F = Kx
K = F/x
K = 1/0.14
K = 7.143 lbf/in
Now, if the spring deflection is 1.8in
Then, the force applied is
F = kx
F = 7.143 × 1.8
F = 12.857 lbf
Now, this force is equal to the weight of the body
And weight of the body can be determined using.
W = mg
Therefore,
m = W/g
m = 12.857 / 31
m = 0.415 lb
The mass of the object is 0.415 pounds