Answer:
Explanation:
Fx = F₁ cos62 + F₂cos 53.7
= -(9.8cos 62 + 5.2 cos 53.7 )
= - ( 4.6 + 3.07
= - 7.67 N
Fy = F₁ sin 62 - F₂sin 53.7
= 9.8 sin 62 - 5.2 sin 53.7
= 8.65 - 4.19
= 4.46 N
c )
magnitude of resultant F
= √ ( Fx² + Fy²)
= √ ( 7.67² + 4.46²)
= √ ( 58.83 + 19.89)
= 8.87 N
d )
Tanγ = Fy / Fx
= 4.46 / 7.67
.58
γ = 30° approx .
Answer:
a) m=20000Kg
b) v=0.214m/s
Explanation:
We will separate the problem in 3 parts, part A when there were no coals on the car, part B when there is 1 coal on the car and part C when there are 2 coals on the car. Inertia is the mass in this case.
For each part, and since the coals are thrown vertically, the horizontal linear momentum p=mv must be conserved, that is,
, were each velocity refers to the one of the car (with the eventual coals on it) for each part, and each mass the mass of the car (with the eventual coals on it) also for each part. We will write the mass of the hopper car as
, and the mass of the first and second coals as
and
respectively
We start with the transition between parts A and B, so we have:

Which means

And since we want the mass of the first coal thrown (
) we do:



Substituting values we obtain

For the transition between parts B and C, we can write:

Which means

Since we want the new final speed of the car (
) we do:

Substituting values we obtain

The reason weather balloons are only partially inflated is to allow room for the helium in the balloon to expand.
The dipole moment of a molecule and its boiling point are directly varied. If the dipole moment is large, the attraction between the positive and negative charges of a molecule is strong thus, requiring stronger forces to break them. Hence, they will have higher boiling points.
<span>1.) It is 6.00km from your home to the physics lab. As part of your physical fitness program, you could run that distance at 10.0km/hr (which uses up energy at the rate of 700W ), or you could walk it leisurely at 3.00km/hr (which uses energy at 290 W).
A.)Which choice would burn up more energy?
running or walking?
b.)How much energy (in joules) would it burn?
c.)Why is it that the more intense exercise actually burns up less energy than the less intense one?
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Answers
billrussell42
Best Answer: running, at 10 km/hour for 6 km is
6 km / 10 km/hour = 0.6 hour or 36 min
energy used is 700 watts or 700 joules/s x 36 min x 60s/min = 1.512e6 joules or 1.5 MJ
walking, at 3 km/hour for 6 km
6 km / 3 km/hour = 2 hour or 120 min
energy used is 290 watts or 290 joules/s x 120 min x 60s/min = 1.872e6 joules or 1.8 MJ
C) should be obvious
PS, this has nothing to do with potential energy.
billrussell42 · 5 years ago
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Simon van Dijk
I assume the watt consumption is per hour. Then running 6km at 10.0 km/h results in 700*6/10 = 420 w.h and walking in 290*6/3 = 580 w.h So walking would burn up more energy (kwh)
b) 1 kilowatt hour = 3 600 000 joules
so 420 wh = 0.42 kwh = 1.51.10^6 joule
c) when you put more effort in making the distance your energy is used more efficient.
Simon van Dijk · 5 years ago
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