Acceleration occurs whenever the direction or the speed changes
Answer:
r₂ = 0.2 m
Explanation:
given,
distance = 20 m
sound of average whisper = 30 dB
distance moved closer = ?
new frequency = 80 dB
using formula

I₀ = 10⁻¹² W/m²
now,



to hear the whisper sound = 80 dB



we know intensity of sound is inversely proportional to square of distances



r₂ = 0.2 m
Explanation:
The gravitational potential energy is given by :
P = mgh
The kinetic energy of an object is given by :

As the ball reaches the bottom of the ramp, its potential energy decreases and kinetic energy increases.
It imply that, when the ball at the top most height, its gravitational potential energy is maximum and zero kinetic energy and when ball reaches the bottom of the ramp, it will have maximum kinetic energy and zero potential energy.
Answer:
Electric Motor
Explanation:
There are mainly two types of machines for inter-conversion between mechanical energy and electrical energy as under:
- Motor
- Generator
Motor is a device which converts electrical energy into a mechanical whereas generator does the exact opposite of motor.
There are 2 types of motors:
AC Motor - Converts alternating current into mechanical energy
DC Motor - Converts direct current into mechanical energy
Answer:
1 . rays should passs through correct center or points(i.e. optic center or focus)
2.your line representing rays should be straight and u should tell the nature of image
Explanation: