Answer:
Explanation:
Let h be the height .
initial velocity in first case u = 0
final velocity v = 6 m /s
acceleration due to gravity g = 9.8 m /s²
v² = u² + 2 g h
6² = 0 + 2 x 9.8 x h
h = 1.837 m .
For second case u = 3 m /s
v² = u² + 2 gh
= 3² + 2 x 1.837 x 9.8
= 9 + 36
= 45 m
v = 6.7 m /s
Answer
A. the work done on the refrigerant in each cycle is 105kJ
B the coefficient of performance of the refrigerator is 4.8
Explanation
Given data
Work done at high temperature T2 Qh=610kJ
Work done at low temperature T1 Ql=505kJ
We know that the net work done by the refrigerator is expressed as
Wnet= Qh-Ql
=610-505
=105kJ
Also we know that the coefficient of performance is expressed as
COP= Ql/Wnet
COP= 505/105
= 4.8
882 divided by 9.81 (this is acceleration due to gravity) it equals 89.91
The clicker emits EM (electromagnetic) wave which travels at the speed of light, that is
v = 3 x 10⁸ m/s
The frequency is
f = 900mHz = 9 x 10⁸ Hz
Because velocity = frequency * wavelength, the wavelength, λ, is given by
fλ = v
λ = v/f
= (3 x 10⁸ m/s) / (9 x 10⁸ 1/s)
= 1/3 m
Answer: 1/3 m
Answer:
0.01606 Newtons
Explanation:
r = Distance between the asteroid and Sally = 17000000 m
m₁ = Mass of the asteroid = 8.7× 10²⁰ kg
m₂ = Mass of Sally = 80 kg
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
From Newton's Universal law of gravity

The force Sally experiences is 0.01606 Newtons