1. What is the weight of this objects?
Weight is simply the product of mass and gravitational
acceleration. Therefore the weight is:
w = 20 kg * 9.81 m/s^2
w = 196.2 kg m/s^2 = 196.2 N
2. After 5 seconds, how has the object fallen and what is its
speed at this instant?
We can use the formula:
<span>y = v0 t + 0.5 g
t^2</span>
v = v0 + g t
where v0 = 0 since the object starts from rest, y is the
distance it fell, t is time
y = 0 + 0.5 * 9.81 * 5^2 = 122.625 m
<span>v = 0 + 9.81 * 5 = 49.05 m/s</span>
The acceleration of gravity is inversely proportional to
the square of the distance from Earth's center.
The acceleration of gravity is 9.8 m/s² on the Earth's surface ...
6380 km from the center.
If the acceleration of gravity at 'h' is 4.9 m/s² ... 1/2 of what it is
on the surface, then the distance from the center is
(6380 x √2) = 9,023 km (rounded) ,
and 'h' is the distance above the surface
= (9,023 - 6,380) = 2,643 km (rounded) .
60 minutes = 1h
500/x = 10/100
She swam 5 kilometers per hour.
Apply the combined gas law
PV/T = const.
P = pressure, V = volume, T = temperature, PV/T must stay constant.
Initial PVT values:
P = 1atm, V = 8.0L, T = 20.0°C = 293.15K
Final PVT values:
P = ?, V = 1.0L, T = 10.0°C = 283.15K
Set the PV/T expression for the initial and final PVT values equal to each other and solve for the final P:
1(8.0)/293.15 = P(1.0)/283.15
P = 7.7atm
