To solve this problem we will apply the concepts related to the conservation of momentum. The momentum can be defined as the product between the mass of the object and its velocity, and the conservation of the momentum as the equality between the change of the initial momentum versus the final momentum. Mathematically, this relationship can be described as
Here,
= Mass of each object
= Initial velocity of each object
= Final velocity of each object
According to the statement one of the bodies does not have initial velocity, therefore said term would be zero. And the equation could be rewritten as,
Replacing the values respectively (The mass of your body with its respective speed we would have)
Therefore the initial velocity of the 2kg cart is 0.55m/s
Answer:
option (e) is correct.
Explanation:
mass of adult, M = 81 kg
Gravitational Potential energy of adult, U = 2000 J
Let the height raised is h.
U = mass of adult x g x h
2000 = 81 x 9.8 x h
h = 2.52 m
mass of adult, m = 18 kg
height raised, h = 2.52 m
Potential energy of child, U' = m x g x h
U' = 18 x 2.52 x 9.8 = 444.44 J
Thus, option (e) is correct.
Answer:
Velocity of Afrom B=21m/s
Acceleration of A from B=1.68m/s°2
Explanation:
Given
Radius r=150m
Velocity of a Va= 54km/hr
Va=54*1000/3600=15m/s
Velocity of b Vb=82km/hr
VB=81*1000/3600=22.5mls
The velocity of Car A as observed from B is VBA
VB= VA+VBA
Resolving the vector into X and Y components
For X component= 15cos60=7.5m/s
Y component=22 5sin60=19.48m/s
VBA= √(X^2+Y^2)
VBA= ✓(7.5^2+19.48^2)=21m/s
For acceleration of A observed from B
A=VA^2/r= 15^2/150=1.5m/s
Resolving into Xcomponent=1.5cos60=0.75m/s
Y component=3cos60=1.5
Acceleration BA=√(0.75^2+1.5^2)
1.68m/s
Answer:
The frequency of radio waves with a wavelength of 20m is
1.5 e+7 Hertz (Hz) or 15 million Hertz.
This was obtained from the formula speed (c) is equal to the product of frequency (f) and wavelength (λ)
c = fλ
Since we are looking for the frequency, we will divide both sides of the formula above by the lamda symbol for wavelength, which gives us:
f = c / λ
The value of wavelength is already given which is 20 meters. The speed of radio waves is the same with the speed of light when travelling in a vacuum – also with the other electromagnetic waves. Hence the speed (c) is 3 e+8 m/s
f = 3 e+8 m/s / 20m
f = 1.5 e+7 H
Explanation:
this is the correct answer you want.