Both a molten metallic core and reasonably fast rotation.
It might make more sense putting it another way but this is basically it. you just take the minutes and divide them by 60 to convert them to hours. then simplify the ratio
Answer:
Power will be 0.2023 watt
And when amplitude is halved then power will be 0.0505 watt
Explanation:
We have given mass of the Piano wire m = 2.60 gram = 0.0026 kg
Length of wire l = 84 cm = 0.84 m
So mass density 
Tension in the wire T = 25 N
Frequency f = 120 Hz
So angular frequency 
And amplitude A = 1.6 mm = 0.0016 m
We have to find the generated power
Power is given by 
From the relation we can see that power 
So if amplitude is halved then power will be
times
So power will be equal to 
Answer: d. 8.25 m/s
Explanation:
We are given that Current= 5 m/s in j direction
Velocity= 8 m/s i + 3 m/s j
Now, we have to find Jada's speed with respect to the water.
First we find Jada's velocity with respect to water
v= (8 i + 3 j) - (5 j)
v= 8i - 2 j
To find the speed, we take the magnitude of this velocity vector we have
|v|= 
|v|=
= 8.246 m/s
which comes out to be around = 8.25 m/s
So option d is correct.