Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately
Answer:
The charge on the dust particle is 
Explanation:
From the question we are told that
The length is 
The width is 
The charge is 
The mass suspended in mid-air is 
Generally the electric field on the carpet is mathematically represented as
Where 
is the permittivity of free space with value 
substituting values
Generally the electric force keeping the dust particle on the air equal to the force of gravity acting on the particles
=> 
=> 
=> 
=>
Answer:
<em>Its speed will be 280 m/s</em>
Explanation:
<u>Constant Acceleration Motion</u>
It's a type of motion in which the speed of an object changes by an equal amount in every equal period of time.
If a is the constant acceleration, vo the initial speed, vf the final speed, and t the time, vf can be calculated as:
The object accelerates from rest (vo=0) at a constant acceleration of 
. The final speed at t=35 seconds is:
Its speed will be 280 m/s
Answer:
case x py L is in the positive z direction
case y px L the negative z direction
Explanation:
The angular amount is defined by the relation
L = r x p
the bold are vectors, where r is the position vector and p is the linear amount vector.
The module of this vector can be concentrated by the relation
L = r p sin θ
the direction of the vector L can be found by the right-hand rule where the thumb points in the direction of the displacement vector, the fingers extended in the direction of the moment p which is the same direction of speed and the palm points in the direction of the angular momentum L
in the case x py
the thumb is in the x direction, the fingers are extended in the direction and the palm is in the positive z direction
In the case y px
the thumb is in the y direction, the fingers are in the x direction, the palm is in the negative z direction
