Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.
Answer:
E = 16 J
Explanation:
Given that,
Mass of a book, m = 2 kg
Velocity of the book from the backpack, v = 4 m/s
We need to find the kinetic energy of the book falling out of the backpack. Due to the motion of the object, kinetic energy is possessed by it. It can be given by :
So, the kinetic energy of the book is 16 J.
Answer:
Speed of physicist car is 0.036c or 1.08 x 10⁷ m/s .
Explanation:
Doppler Effect is defined as the change in frequency or wavelength of the wave as the source or/and observer moving away or towards each other.
In this case, the Doppler effect equation in terms of wavelength is :
......(1)
Here is source wavelength, is observed wavelength, v is speed of the observer and c is the speed of light.
Given :
Source wavelength, = 660 nm = 660 x 10⁻⁹ m
Observed wavelength, = 555 nm = 555 x 10⁻⁹ m
Substitute these values in the equation (1).
v = 1.08 x 10⁷ m/s
Answer:
a direct current goes in one direction at all times whereas an alternating current goes back and forth in a circuit