Answer: 2.86 m
Explanation:
To solve this question, we will use the law of conservation of kinetic and potential energy, which is given by the equation,
ΔPE(i) + ΔKE(i) = ΔPE(f) + ΔKE(f)
In this question, it is safe to say there is no kinetic energy in the initial state, and neither is there potential energy in the end, so we have
mgh + 0 = 0 + KE(f)
To calculate the final kinetic energy, we must consider the energy contributed by the Inertia, so that we then have
mgh = 1/2mv² + 1/2Iw²
To get the inertia of the bodies, we use the formula
I = [m(R1² + R2²) / 2]
I = [2(0.2² + 0.1²) / 2]
I = 0.04 + 0.01
I = 0.05 kgm²
Also, the angular velocity is given by
w = v / R2
w = 4 / (1/5)
w = 20 rad/s
If we then substitute these values in the equation we have,
0.5 * 9.8 * h = (1/2 * 0.5 * 4²) + (1/2 * 0.05 * 20²)
4.9h = 4 + 10
4.9h = 14
h = 14 / 4.9
h = 2.86 m
Answer:
D. Newton's second law
Explanation:
Newton's second law of motion states that force of an object is a product of its mass and its acceleration.
Mathematically, F= ma where m is mass and a is acceleration
So from the statement above : The acceleration of an object is proportional to the force applied to it and inversely proportional to its mass , it can be seen from the formula variation as;
F= ma -----making a the subject of the formula
a= F/ m
a= 1/m * F --------- a is inversely related to m as you can see from 1/m but directly related to F hence;
Increase in mass with the same force applied causes the body to accelerate slower where as when force increases, the body accelerates faster.
A: Buoyant force is equal to the weight
Answer:
while ice is made by water again it melts and becomes water. water is colourless and odourless and has no taste but ice is only cold and hard. water is used for drinking and other things. but is for freshness and it never flows
Explanation:
so ice reflect more energy compared to water