Answer:
3430000 J
Explanation:
The formula for potential energy is PE=mgh.
M being the mass, g being the force of gravity, and h being the height.
First thing you want to do is convert 250 kg to g (grams).
From there you get 25000g and you have to multiply that by 14m and 9.8m/s^2 (the force of gravity is constant, at least on earth).
Explanation:
The distance that a car travels down the interstate can be calculated with the following formula:
Distance = Speed x Time
(A) Speed of the car, v = 70 miles per hour = 31.29 m/s
Time, d = 6 hours = 21600 s
Distance = Speed x Time
D = 31.29 m/s × 21600 s
D = 675864 meters
or
![D=6.75\times 10^5\ m](https://tex.z-dn.net/?f=D%3D6.75%5Ctimes%2010%5E5%5C%20m)
(b) Time, d = 10 hours = 36000 s
Distance = Speed x Time
D = 31.29 m/s × 36000 s
D = 1126440 meters
or
![D=1.12\times 10^6\ m](https://tex.z-dn.net/?f=D%3D1.12%5Ctimes%2010%5E6%5C%20m)
(c) Time, d = 15 hours = 54000 s
Distance = Speed x Time
D = 31.29 m/s × 54000 s
D = 1689660 meters
or
![D=1.68\times 10^6\ m](https://tex.z-dn.net/?f=D%3D1.68%5Ctimes%2010%5E6%5C%20m)
Hence, this is the required solution.
Answer:
37.8 m
Explanation:
At point 0, the ball is at height y₀.
At point 1, the ball is at height 30 m.
At point 2, the ball is at height 0 m.
Given:
y₁ = 30 m
y₂ = 0 m
v₀ = 0 m/s
a = -10 m/s²
t₂ − t₁ = 1.5 s
Find: y₀
Use constant acceleration equation.
y = y₀ + v₀ t + ½ at²
Evaluate at point 1.
y₁ = y₀ + v₀ t₁ + ½ at₁²
30 m = y₀ + (0 m/s) t₁ + ½ (-10 m/s²) t₁²
30 = y₀ − 5t₁²
Evaluate at point 2.
y₂ = y₀ + v₀ t₂ + ½ at₂²
0 m = y₀ + (0 m/s) t₂ + ½ (-10 m/s²) t₂²
0 = y₀ − 5t₂²
y₀ = 5t₂²
Substitute:
y₀ = 5 (1.5 + t₁)²
y₀ = 5 (2.25 + 3t₁ + t₁²)
y₀ = 11.25 + 15t₁ + 5t₁²
30 = 11.25 + 15t₁ + 5t₁² − 5t₁²
30 = 11.25 + 15t₁
t₁ = 1.25
30 = y₀ − 5t₁²
30 = y₀ − 5(1.25)²
y₀ ≈ 37.8
Answer:
b) 16 cm
Magnification, m = v/u
3 = v/u
⇒ v = 3u
Lens formula : 1/v – 1/u = 1/f
1/3u = 1/u = 1/12
-2/3u = 1/12
⇒ u = -8 cm
V = 3 × (-8) = -24
Distance between object and image = u – v = -8 – (-24) = -8 + 24 = 16 cm
Explanation: