Answer:
ma = 48.48kg
Explanation:
To find the mass of the astronaut, you first calculate the mass of the chair by using the information about the period of oscillation of the empty chair and the spring constant. You use the following formula:
(1)
mc: mass of the chair
k: spring constant = 600N/m
T: period of oscillation of the chair = 0.9s
You solve the equation (1) for mc, and then you replace the values of the other parameters:
(2)
Next, you calculate the mass of the chair and astronaut by using the information about the period of the chair when the astronaut is sitting on the chair:
T': period of chair when the astronaut is sitting = 2.0s
M: mass of the astronaut plus mass of the chair = ?
(3)
Finally, the mass of the astronaut is the difference between M and mc (results from (2) and (3)) :

The mass of the astronaut is 48.48 kg
The fatal current is 51 mA = 0.051 Ampere.
The resistance is 2,050Ω .
Voltage = (current) x (resistance)
= (0.051 Ampere) x (2,050 Ω) = 104.6 volts .
==================
This is what the arithmetic says IF the information in the question
is correct.
I don't know how true this is, and I certainly don't plan to test it,
but I have read that a current as small as 15 mA through the
heart can be fatal, not 51 mA .
If 15 mA can do it, and the sweaty electrician's resistance is
really 2,050 Ω, then the fatal voltage could be as little as 31 volts !
The voltage at the wall-outlets in your house is 120 volts in the USA !
THAT's why you don't want to stick paper clips or a screwdriver into
outlets, and why you want to cover unused outlets with plastic plugs
if there are babies crawling around.
Answer:
m v1 = (m + M) v2
v2 = m v1 / (m + M)
v2 = 7 * 74 / (74 + 65)
3.73 m/s
74 kg is too heavy for the cannonball (over 150 lbs)
Answer:

Explanation:
I = Moment of inertia = 
m = Mass of two atoms = 2m = 
r = distance between axis and rotation mass
Moment of inertia of the system is given by

The distance between the atoms will be two times the distance between axis and rotation mass.

Therefore, the distance between the two atoms is 