Answer:
Explanation:
We shall find electric field at origin due to two given charges sitting on the either side of origin .
Total field will add up due to their same direction .
Field due to a charge Q
= 9 x 10⁹ x Q / R² ; R is distance of point , Q is charge
Field due to first charge
= 9 x 10⁹ x 40 x 10⁻³ / 2² x 10⁻⁴
= 90 x 10¹⁰ N/C
Field due to second charge
= 9 x 10⁹ x 50 x 10⁻³ / 2² x 10⁻⁴
= 112.5 x 10¹⁰ N/C
Total field
= 202.5 x 10¹⁰ N/C
Force on given charge at origin
= charge x field
= 4 x 10⁻³ x 202.5 x 10¹⁰
= 810 x 10⁷ N .
<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>
Answer:
116.1 kgm²/s
1.12718 rad/s
Decreases
Explanation:
m = Mass of girl = 43 kg
M = Mass of roundabout = 120 kg
v = Velocity of roundabout = 2.7 m/s
r = Radius of roundabout = 1 m = R
I = Moment of inertia
Her angular momentum

Magnitude of angular momentum is 116.1 kgm²/s
Here the angular momentum is conserved

Angular speed of the roundabout is 1.12718 rad/s
Initial kinetic energy

Final kinetic energy

The overall kinetic energy decreases as can be seen. This loss is converted to heat.
The ball is going Zero miles right before the player kicks it.
The potential energy would be holding the yo-yo as the kinetic would be throwing it down and getting it back up