Answer:

Explanation:
From the question we are told that:
Force
Time 
Length of pedal 
Radius of wheel 
Moment of inertia, 
Generally the equation for Torque on pedal
is mathematically given by


Generally the equation for angular acceleration
is mathematically given by



Therefore Angular speed is \omega



Generally the equation for Tangential velocity V is mathematically given by



This question wants a conversion
90km = 90000m
1hr = 3600 seconds
90000m/3600s= 900/36
= 25m/s
Answer:
W and X
Explanation:
When escaping a rip current, one should always walk to the side until you escape from the rip current. If you walk towards the shore, you have the ability to keep getting dragged toward the current, such as with X and Y.
Answer:

Explanation:
The Coulomb's Law gives the force by the charges:

Let us denote the positon of the charge q on the y-axis as 'y'.
The force between 'Q' and'q' is

where Θ is the angle between
and x-axis.

whereas

Finally, the x-component of the net force is

Answer:
1.35 V
Explanation:
Given:
Capacitance of the capacitor (C) = 1.3 μF = ![1.3\times 10^{-6}\ F\ \ [1\mu F=10^{-6}\ F]](https://tex.z-dn.net/?f=1.3%5Ctimes%2010%5E%7B-6%7D%5C%20F%5C%20%5C%20%5B1%5Cmu%20F%3D10%5E%7B-6%7D%5C%20F%5D)
Frequency (f) = 3.9 kHz= 3.9 × 1000 Hz = 3900 Hz [1 kHz = 1000 Hz]
Current flowing in the circuit (I) = 43 mA = 0.043 A [1 mA = 0.001 A]
Now, as only capacitor is there in the circuit, the impedance of the circuit is equal to the reactance of the capacitor.
So, 
The reactance of the capacitor is given as:

Plug in the values given and solve for
. This gives,

Therefore, the impedance is, 
Now, the voltage needed to create the given current is obtained using the formula from Ohm's law and is given as:

Therefore, the voltage needed to create a current of 43 mA is 1.35 V.