Answer:
<em>Both kinetic energies are equal</em>
Explanation:
<u>Kinetic Energy
</u>
Is the type of energy of an object due to its state of motion. It's proportional to the mass and the square of the speed.
The equation for the kinetic energy is:
Where:
m = mass of the object
v = speed of the object
The kinetic energy is expressed in Joules (J)
There are two cars:
Car (A) with mass ma=500 kg and speed va= 2 m/s
Car (B) with mass mb=20,000 gr and speed vb= 10 m/s
Calculate the kinetic energy of both cars:
To calculate the Kb, the mass must be expressed in kg:
mb=20,000/1,000 =20 Kg
Both kinetic energies are equal
Punching a bag is a suitable example of the situation when the force applied to change shape of an object.
Answer:
V1 =8.1 m/s
Explanation:
height at highest point (h2) = 4.1 m
height at lowest point (h1) = 0.8 m
acceleration due to gravity (g) = 9.8 m/s^{2}
from conservation of energy, the total energy at the lowest point will be the same as the total energy at the highest point. therefore
mgh1 + 
= mgh2 + 
where
- speed at highest point = V2
- speed at lowest point = V1
- mass of the girl and swing = m
- at the highest point, the speed is minimum (V1 = 0)
- at the lowest point the speed is maximum (V2 is the maximum speed)
- therefore the equation becomes mgh1 + = mgh2
m(gh1 + 
) = m(gh2)
gh1 + = gh2
V1 = 
now we can substitute all required values into the equation above.
V1 = 
V1 = 
V1 =8.1 m/s
An VIRTUAL image cannot be projected, and
forms where light rays appear to originate.
Answer:
See solution below
Explanation:
The standard equation of a wave is represented by: Y = Asin 2π(x/λ – ft)
A is the amplitude
λ is the wavelength
f is the frequency
t is the time
Comparing the standard with the given equation Y = 0.005sin 2π(0.5x – 200t)
i) A = 0.005m
Amplitude is 0.005m
ii) ω = 2πf
ω = 2π(200)
ω = 400π rad/s
iii) ω = 2πf
400π = 2πf
200 = f
Swap
f = 200Hertz
iv) Period = 1/f
Period = 1/200
Period = 0.005secs
v) wave number =
vi) Wavelength λ
0.5x = x/λ
0.5 = 1/λ
λ = 1/0.5
λ = 2m
vii) velocity - fλ
velocity = 200 * 2
velocity = 400m/s
