Choice 'D' describes speed in the metric units 'meter' and 'second'.
With no mention of direction, it can't be called 'velocity'.
<span>Total KE = KE (rotational) + KE (translational)
Moment of inertia of sphere is I = (2/5)mr^2
So KE (rotational) = (1/2) x I x w^2 = (1/2) x (2/5)mr^2 x w^2 = (1/5) x m x r^2 x w^2
KE (translational) = (1/2) x m x v^2 = (1/2) x m x (rw)^2 = (1/2) x m x r^2 x w^2
Hence KE = (1/5) x m x r^2 x w^2 + (1/2) x m x r^2 x w^2 = m x r^2 x w^2 ((1/5) + (1/2))
KE = (7/10) m x r^2 x w^2
Calculating the fraction of rotational kinetic energy to total kinetic energy,
= rotational kinetic energy / total kinetic energy
= (1/5) x m x r^2 x w^2 / (7/10) m x r^2 x w^2 = (1/5) / (7/10) = 2 / 7
The answer is 2 / 7</span>
We know the formulas for momentum and energy. But they both involve the mass of
the object, and we don't know the mass of the baseball. What can we do ?
It's not a catastrophe. The question only asks which one is bigger. If we're clever,
we can answer that without ever knowing how much the momentum or the energy
actually is. We know that both baseballs have the same mass, so let's just call it
' M ' and not worry about what it really is.
<u>Momentum of anything = (mass) x (speed)</u>
Momentum of the first baseball = (M) x (4 m/s) = 4M
Momentum of the second one = (M) x (16 m/s) = 16M
The second baseball has 4 times as much momentum as the first one has.
<u>Kinetic energy of anything = 1/2 (mass) x (speed squared)</u>
KE of the first baseball = 1/2 (M) x (4 squared) = 8M
KE of the second one = 1/2 (M) x (16 squared) = 128M
The second baseball has 16 times as much kinetic energy as the first one has.
Answer:
The most common type of descriptive research is the case study, which provides an in-depth analysis of a specific person, group, or phenomenon.
Answer:
It reflects in a certain way which can either mirror or crystalize which basically is becoming see-through.
Explanation: