Answer
given,
mass of the hiker = 66.5 kg
elevation of the hiker,h₁ = 1270 m
elevation of top peak,h₂ = 2660 m
a) Change in potential energy
Δ PE = m g h₂ - m g h₁
Δ PE = m g (h₂ - h₁)
Δ PE = 66.5 x 9.8 x (2660 - 1270)
Δ PE = 905863 J
b) Minimum work require by the hiker will be equal to Δ PE = 905863 J
c) yes, it can be more than this, if friction is present on the surface.
Answer:
So then we will have that the 3 working together will complete 1 job in approximately 1.429 hours for this case.
Explanation:
If we want to express the situation in math terms and find the number of hours that takes to complete 1 job with the 3 at the same time, we can do this.
For this case we have the following rates:
And we know that working together the rate would be the addition of the rates like this:
And if we divide the numerator and denominator by 7 we got:
So then we will have that the 3 working together will complete 1 job in approximately 1.429 hours for this case.
resolve speed horizontally and vertically.
apply kinematc equations to calculate "up and dow" vertical motion. You want the round trip time.
apply distance = speed x time to horizontal motion
The energy if of a photon is (Planck's Konstant) x (frequency).
Planck's Konstant is 6.62607004 × 10⁻³⁴ m²-kg/s .
So the photon's energy is
(6.626 × 10⁻³⁴ m²-kg/s) x (4.89 x 10¹⁴ / sec)
= (32.4 x 10⁻²⁰) m²-kg/s²
= 3.24 x 10⁻¹⁹ joule
Answer:
The speed of the kid and the skateboard together is 0.723 m/s
Explanation:
Let the mass of the kid be
Let the mass of the skateboard be
The initial speed of the skateboard,
The initial horizontal speed of the boy as he jumps on the skateboard,
Let the speed of the kid and the skateboard together be v
According to the principle of conservation of momentum:
Substituting the appropriate values into the given equation
36 = 49.8 v
v = 36/49.8
v = 0.723 m/s