<span>At first when the car is at the datum
point where is no elevation, the kinetic energy increases while the potential
energy is zero. As it travel the path and goes upward the kinetic enrgy
decreases while the potential energy increases. When it goes down again the
kinetic enrgy increases again while the potential energy decreases </span>
<span>Since there is no friction, conservation of energy gives change in energy is zero
Change in energy = 0
Change in KE + Change in PE = 0
1/2 x m x (vf^2 - vi^2) + m x g x (hf-hi) = 0
1/2 x (vf^2 - vi^2) + g x (hf-hi) = 0
(vf^2 - vi^2) = 2 x g x (hi - hf)
Since it starts from rest vi = 0
Vf = squareroot of (2 x g x (hi - hf))
For h1, no hf
Vf = squareroot of (2 x g x (hi - hf))
Vf = squareroot of (2 x 9.81 x 30)
Vf = squareroot of 588.6
Vf = 24.26
For h2
Vf = squareroot of (2 x 9.81 x (30 – 12))
Vf = squareroot of (9.81 x 36)
Vf = squareroot of 353.16
Vf = 18.79
For h3
Vf = squareroot of (2 x 9.81 x (30 – 20))
Vf = squareroot of (20 x 9.81)
Vf = 18.79</span>
The correct answer is C , because the space is vacuum and his body can explode and for this reason, the astronaut need a special costum to be protected. It's the same on the moon, because there is no atmosphere
The formula for the mass that remains:
m₀ - the initial mass, t - time, T - the half-life
The answer is c. 1.25 g.
Answer:
I don't know about these problems at all.
Explanation:
I don't know about physics at all
