Answer:
16.2 days
Explanation:
Find the number of halflives:
1/2 * 1/2 = 1/4 so <u>two</u> halflives have passed
2 * 8.1 days = 16.2 days
When a ball is whirled using a string, it is restricted to move only in circular motion because the net force acting on the ball is towards the center of the circle. Hence, the acceleration of the ball is towards the center. But the velocity of ball is tangential to this circular path all the time. When the whirling is stropped, the string becomes slack and tension in the string becomes zero. The ball no more performs circular motion and the ball moves tangentially to the circle in straight line. Therefore, before letting go, velocity was variable. After letting go, velocity becomes constant.
The particles vibrate against each other in a soild state........i think
Answer:
42 m/s
Explanation:
by definition of the velocity(speed) of a wave,
The velocity of light, v, is the product of its wavelength, λ , and its frequency, f.
V= fλ
frequency - number of occurances in a unit time
(check the graph)
