Answer:
When you climb, earth exerts gravitational force on pack in downward direction(pointing towards the center of earth).
In order to climb, you need to work against work done by gravity on the pack.
Hence work done by you = work done by gravity on pack
= Force x displacement = 70 x 30 = 2100 J.
So you need to do 2100 joules of work to lift your pack.
Power is the rate of work done.
Therefore power = work done by you/time(in seconds)
= 2100/600 =3.5 watts
Explanation:
Answer: D
Explanation:
Atomic weight is measured by adding the number of protons and neutrons in an atom's nucleus. Argon's atomic number is 18 while potassium's is 19. This means that Argon will always have 18 protons while potassium will always have 19 protons.
To make the numbers easier to work with, round each atomic weight. We'll say the atomic weight of potassium is 39 and the atomic weight of argon is 40. To see how many neutrons each one has, I can set up a simple equation for each using the following equation:
Atomic weight = protons + neutrons
Potassium:
39 = 19 + N --> N = 20
Argon:
40 = 18 + N --> N = 22
An atom is defined by the number of protons it has, but the number of neutrons can vary. We call these isotopes, or atoms with the same number of protons but a different number of neutrons. As the math shows, argon typically has more neutrons per atom than potassium does.
Given
Car 1
m1 = 1300 kg
v1 = 20 m/s
m2 = 900 kg
v2 = -15 m/s
(Negative sign shows that direction of car 2 is opposite to car 1)
Procedure
As per the conservation of linear momentum, "The total momentum of the system before the collision must be equal to the total momentum after the collision". And this applies to the perfectly inelastic collision as well. Then the expression is,
Thus, we can conclude that the speed and direction of the cars after the impact is 5.68 m/s towards the first car.
Your body continues to move unless stopped by the seatbelt. An object in motion will remain in motion. Since your body was already moving it will continue to.
Answer:
x_total = (A + B) cos (wt + Ф)
we have the sum of the two waves in a phase movement
Explanation:
In this case we can see that the first boy Max when he enters the trampoline and jumps creates a harmonic movement, with a given frequency. When the second boy Jimmy enters the trampoline and begins to jump he also creates a harmonic movement. If the frequency of the two movements is the same and they are in phase we have a resonant process, where the amplitude of the movement increases significantly.
Max
x₁ = A cos (wt + Ф)
Jimmy
x₂ = B cos (wt + Ф)
total movement
x_total = (A + B) cos (wt + Ф)
Therefore we have the sum of the two waves in a phase movement
