The electric force between charged bodies decreases by a factor equal to the relative permittivity, ie:
F ∝ 1/ε
F = electric force, ε = relative permittivity
Find the scaling factor of F due to the change in ε:
k = 1/(0.9/0.45) = 1/2 = 0.5
Multiply the original F by k to find the new F:
F = 0.8N×k
F = 0.8N×0.5
F = 0.4N
Answer
given,
mass of baseball(m) = 144 g = 0.144 Kg
initial velocity(u) = 29 m/s
mass of brick(M) = 5.25 Kg
speed of the brick (v') = 1.32
speed of base ball after collision = ?
using conservation of momentum
m u = m v + Mv'
0.144 x 29 = 0.144 v + 5.25 x 1.32
0.144 v = -2.754
v = -19.125 m/s
b) KE before collision
KE_i = 60.55 J
KE after collision
KE_f = 30.91 J
Answer:
5.44×10⁶ m
Explanation:
For a satellite with period t and orbital radius r, the velocity is:
v = 2πr/t
So the centripetal acceleration is:
a = v² / r
a = (2πr/t)² / r
a = (2π/t)² r
This is equal to the acceleration due to gravity at that elevation:
g = MG / r²
(2π/t)² r = MG / r²
M = (2π/t)² r³ / G
At the surface of the planet, the acceleration due to gravity is:
g = MG / R²
Substituting our expression for the mass of the planet M:
g = [(2π/t)² r³ / G] G / R²
g = (2π/t)² r³ / R²
R² = (2π/t)² r³ / g
R = (2π/t) √(r³ / g)
Given that t = 1.30 h = 4680 s, r = 7.90×10⁶ m, and g = 30.0 m/s²:
R = (2π / 4680 s) √((7.90×10⁶ m)³ / 30.0 m/s²)
R = 5.44×10⁶ m
Notice we didn't need to know the mass of the satellite.
Answer:
it shows examples of types of forces
Answer:
173.45 K
Explanation:
This an Adiabatic process because no energy is lost by thermal conduction on expansion. We will be using this Adiabatic condition and ideal gas equation to solve the question.
From idea gas equation;
PV = nRT
-----(1)
where
P is pressure of the gas
V is volume of the gas
n is number of moles
R is gas constant 8.31441 J K-1 mol-1.
T is temperature in Kelvin
For Adiabatic Condition;
----(2)
Substituting equation(1) into equation(2)
Eliminating the constants and simplify with exponent
Making T₂ the subject of the formula;
The temperature when the initial volume has quadrupled ⇒ V₂ = 4V₁
⇒
Since air is diatomic, we assume k = 1.4
∴
T₂ = 173.45 K