Answer:
Explanation:
Given that,
Force applied to pedal F = 50N
Angular velocity ω = 10rev/s
We know that, 1rev = 2πrad
Then, ω = 10rev/s = 10×2π rad/s
ω = 20π rad/s
Length of pedal r = 30cm = 0.3m
Power?
Power is given as
P = τ×ω
We need to find the torque τ
τ = r × F
Since r is perpendicular to F
Then, τ = 0.3 × 50
τ = 15 Nm
Then,
P = τ×ω
P = 15 × 20π
P = 942.48 Watts
power delivered to the bicycle by the athlete is 942.48 W
Answer:
What is a Pure Substance?
Explanation:
It is something which cannot be divided into parts by physical means, as it's all made up of the same thing. Pure substances are either elements or compounds. Elements can NOT be separated into other types of matter (physically or chemically).
Heat because in a machine heat must come out to follow the law of conservation of energy
An object need to move in a straight line in the same direction in equal intervals of time in order for total distance traveled and displacement to be equal.
Answer: 96N
Explanation:
To calculate the velocity of the impact On the persons head, we have
h = gt²/2
14 = 9.81t²/2
t² = 28/9.8
t² = 2.86
t = 1.69s
V = u + at
V = 0 + 9.81*1.69
V = 16.58m/s
a(average) = (v1² + v2²) /2Δy
a(average) = 16.58² + 0)/2 * 0.005
a(average) = 274.8964/0.01
a(average) = 27489.64m/s²
Using newton's second law of motion,
F(average) = m * a(average)
F(average) = 0.0035 * 27489.64
F(average) = 96.21N
Therefore the force needed by the acorn to do much damage starts from 96N