We know there’s a change in momentum due to a force applied over a time interval. Ft= m[v(final)-v(initial)]. Now simply plug in know values: (45)(0.02)=.005[v(final)-0]. Remember converting grams to kilograms. Solve for v final
Answer:
The answer would be A. The waves that heat a cup of water in a microwave oven
The need to quickly move through dark environments. <span />
Ok, assuming "mj" in the question is Megajoules MJ) you need a total amount of rotational kinetic energy in the fly wheel at the beginning of the trip that equals
(2.4e6 J/km)x(300 km)=7.2e8 J
The expression for rotational kinetic energy is
E = (1/2)Iω²
where I is the moment of inertia of the fly wheel and ω is the angular velocity.
So this comes down to finding the value of I that gives the required energy. We know the mass is 101kg. The formula for a solid cylinder's moment of inertia is
I = (1/2)mR²
We want (1/2)Iω² = 7.2e8 J and we know ω is limited to 470 revs/sec. However, ω must be in radians per second so multiply it by 2π to get
ω = 2953.1 rad/s
Now let's use this to solve the energy equation, E = (1/2)Iω², for I:
I = 2(7.2e8 J)/(2953.1 rad/s)² = 165.12 kg·m²
Now find the radius R,
165.12 kg·m² = (1/2)(101)R²,
√(2·165/101) = 1.807m
R = 1.807m
Total internal reflection causes light to be completely reflected across the boundary between the two media but not transmitted.
<h3>What is total internal reflection?</h3>
The term total internal reflection occurs when light is moving from a denser to a less dense medium such as from glass to air. This phenomenon occurs at the interface between the two media.
There are two conditions necessary for total internal reflection and they are;
1) Light must travel from a denser to a less dense medium
2) The angle of incidence in the denser medium must be greater than the critical angle.
Total internal reflection causes light to be completely reflected across the boundary between the two media but not transmitted.
Learn more about total internal reflection:brainly.com/question/13088998
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