Because the coefficient of friction depends on the surface
The product of (frequency) times (wavelength) is always
the same number (the speed of the wave).
So if the frequency is doubled, the wavelength has to drop to
half of what it was, in order to keep their product constant.
Answer:
7.01yard/sec
Explanation:
Given parameters:
Initial position = 50yard
Final position = 12yard
Time = 5.42s
Unknown:
Average speed of runner = ?
Solution:
To solve this problem;
Speed = 
Distance covered = Initial position - final position = 50 - 12 = 38yards
So;
Speed = 
= 7.01yard/sec
Answer:
Explanation:
charge transferred to sphere = 12 - 8 = 4 nC
a )
The positive charge is decreased on glass rod , that means electrons must have entered the glass rod from the sphere which reduces its positive charge.
b )
charge transferred = 4 nC = 4 x 10⁻⁹ C
charge on one electron = 1.6 x 10⁻¹⁹ C
No of electrons transferred
= Total charge transferred / charge on one electron
= 4 x 10⁻⁹ / 1.6 x 10⁻¹⁹
= 2.5 x 10¹⁰ .
(198,000 joule / 15 minute) x (minute / 60 sec) = 220 joule/sec = <em>220 watts
</em>
