Answer:
120 rpm
Explanation:
I1 = 105 kgm^2, I2 = 70 kgm^2
f1 = 80 rpm, f2 = ?
Let the angular speed be f2 when his arms are tucked.
If no external torque is applied, then the angular momentum remains constant.
L1 = L2
I1 w1 = I2 w2
I1 x 2 x 3.14 x f1 = I2 x 2 x 3.14 x f2
105 x 80 = 70 x f2
f2 = 120 rpm
<span>If an electrostatically charged balloon is brought near other objects,
then ...
-- It will be attracted to objects of the opposite charge.
and
-- It will be attracted to objects with a neutral charge.</span>
Answer:
All the meteors in a meteor shower typically come from the same comet, which is in a periodic orbit around the Sun. The dust from the comet follows the path of the parent body and as Earth intersects the debris along the comet's orbit, it plows into this material. Since the dust particles are all moving together in space before they encounter Earth, if you trace back the streak of each meteor, its path will appear to diverge from one place in the sky.
Answer:
Explanation:
Given data:
first case
Distance of electric field from center of sphere is r_1 <R
Electric field at r_1< R
second case
Distance of electric field from centre of sphere is r_1 < 2R
Electric field at r_1< 2R
so, we have