Answer:
D) Insects would have trouble walking on the water.
Explanation:
Answer:
α = -π/3 rad/s²
θ = 1.5π rad ≈ 4.71 rad
θ = 0.75 rev
Explanation:
30 rev/min (2π rad/rev) / (60 s/min) = π rad/s
α = (ωf - ωi) / t = (0 - π) / 3 = -π/3 rad/s²
θ = ½αt² = ½(π/3)3² = 1.5π rad ≈ 4.71 rad
θ = 1.5π rad / 2π rad/rev = 0.75 rev
Well,
A control in an experiment would basically be the "normal" version of your test subjects.
In a drug testing experiment with people, the control group would be the people who don't take the drug.
In an experiment on the effects of salt on potatoes, the control group would be a potato without salt on it.
So in an experiment to measure the effects of gas additives on fuel, the control would be fuel without additives.
<h2>
Power of cheetah is 5576.85 W = 7.48 hp</h2>
Explanation:
Power is the ratio of energy to time.
Here we need to consider kinetic energy,
Mass, m = 102 kg
Initial velocity = 0 m/s
Final velocity = 16.2 m/s
Time, t = 2.4 s
Initial kinetic energy = 0.5 x Mass x Initial velocity² = 0.5 x 102 x 0² = 0 J
Final kinetic energy = 0.5 x Mass x Final velocity² = 0.5 x 102 x 16.2² = 13384.44 J
Change in energy = Final kinetic energy - Initial kinetic energy
Change in energy = 13384.44 - 0
Change in energy = 13384.44 J
Power = 13384.44 ÷ 2.4 = 5576.85 W = 7.48 hp
Power of cheetah is 5576.85 W = 7.48 hp
Given that,
Mass of the stone, m = 400 g = 0.4 kg
Initial speed, u = 20 m/s
It is climbed to a height of 12 m.
To find,
The work done by the resistance force.
Solution,
Let v is the final speed. It can be calculated by using the conservation of energy.
Work done is equal to the change in kinetic energy. It can be given as follows :
So, the required work done is 32.99 J.
