Answer: t = 0.492τ
Explanation: In a circuit where there is a resistor and a capacitor, the equation for a charging capacitor is given by:

where:
is the equilibrium charge
q is the charge at time t
RC is time constant also called τ (tau)
For this problem, the circuit is charged to 39%, which means: q = 

0.39 = 1 - 
= 0.61
= ln(0.61)
-t = ln(0.61)τ
t = 0.492τ
For the condition to be met it is needed 0.492 time constants must elapse.
Torque of F1 = 30*0.025 = 0.75Nm anticlockwise
Torque of F2 = 34 * 0.020 = 0.68Nm clockwise
Horizontal component of F3:
cos 50 = x/20
x = 12.856 N
Torque of F3 horizontal component = 12.856 * 0.01 = 0.129Nm anticlockwise
0.129 + 0.75 - 0.68 = 0.199Nm anticlockwise
sorry I'm not sure is it correct
You can poach an egg which enfolded boiling water and stirring it and dropping a cracked egg in the water until it is fully cooked or you could hard boil and egg by boiling water and letting it cook 5,6 minutes tell you have a soft yellow center or which ever way you prefer
Think of it this way:
-- Any time you have something that means (some number) PER UNIT,
it doesn't matter how many units there are on the table or in the bucket,
because that amount doesn't change the (number) PER UNIT.
-- If oranges cost $1 PER POUND, it doesn't matter how many pounds
you buy, the whole bagful is still $1 PER POUND.
-- If a certain salad dressing has 40 calories PER Tablespoon, it doesn't
matter whether you eat a drop of it or drink the whole jar. You still get
40 calories PER Tablespoon.
-- Density means '(mass) PER unit of volume'. Whether you have a tiny
chip of the substance or a whole truckload of it, there's still the same
amount of mass IN EACH unit of volume.