Mechanical energy E = mgh + 1/2mv²
When he starts, let h = 0 ⇒ E₁ = 1/2mv₁²
When he reaches height h ⇒ E₂ = mgh + 1/2mv₂²
Without friction, energy is conserved at all times.
E₁ = E₂
↓
1/2mv₁² = mgh + 1/2mv₂²
↓
1/2v₁² = gh + 1/2v₂²
↓
gh = 1/2(v₁² - v₂²)
↓
h = (v₁² - v₂²) / (2g)
Answer:
The required diagram is shown in the figure. When an object is placed in front of the convex lens, i.e., between 2F
1
and F
1
, its image is formed beyond 2F
2
on the other side of the lens. The image is real, inverted and enlarged.
solution
Regardless of what direction an object is moving, the acceleration
due to gravity is always directed toward the center of the Earth.
That's the direction commonly known as "down".
Answer:
When the parachute opens, the air resistance increases. The skydiver slows down until a new, lower terminal velocity is reached.