As we know that in transformers we have

here we know that



now from above equation we will have



Answer:

Explanation:
It is given that,
Angular speed of the football spiral, 
Radius of a pro football, r = 8.5 cm = 0.085 m
The velocity is given by :


v = 3.68 m/s
The centripetal acceleration is given by :



So, the centripetal acceleration of the laces on the football is
. Hence, this is the required solution.
Gold’s molar mass is about 196 while aluminum is about 27, thus 50cm of gold has more mass
Answer:
240 V
Explanation:
number of turns in primary coil, Np = 10
Number of loops in secondary coil, Ns = 20
Voltage in primary coil, Vp = 120 V
Let the voltage in secondary coil is Vs.
So, Vs / Vp = Ns / Np
Vs / 120 = 20 / 10
Vs / 120 = 2
Vs = 240 V
Thus, the voltage in secondary coil is 240 Volt.
<h3><u>Answer</u> :</h3>
Initial velocity = zero (i.e., free fall)
Final velocity = 30m/s
Acceleration due to gravity = 10m/s²
For a body falling freely under the action of gravity, g is taken positive
◈ <u>First equation of kinenatics</u> :
⇒ v = u + gt
⇒ 30 = 0 + 10t
⇒ t = 30/10
⇒ <u>t = 3s</u>
Hence, object will attain a speed of 30m/s after 3s.