Looking at decibel scale tables on internet, a "quiet whisper 1 meter away" is generally reported to have a sound intensity of about 20 dB, while a jackhammer 3 meters away produces a sound of about 100 dB of intensity, so option a) could be the correct one.
However, the other options could be considered correct as well, because without knowing the exact sound power produced by the whisper or by the jackhammer it's impossible to calculate the exact sound intensity with precision, and since the values reported in the three options are very similar, all the three of them can be considered as valid.
I thinks it’s A, tell me if you get it right
Answer:
75 N
Explanation:
t = Time taken = 2 seconds
u = Initial velocity
v = Final velocity
s = Displacement = 30 m
a = Acceleration
The acceleration due to gravity on the planet is 15 m/s²
Force
F = ma
The gravitational force exerted on the object near the planet’s surface is 75 N
Answer : a quantitative description of kinematics involves using position , time velocity and acceleration to describe the motion.
Explanation : Kinematics are mostly concerned with the geometrically possible motion of an object without consideration of the force and mass involved.
it is used to describe the position of the object , their velocities, time and their acceleration.
we know the equations of motion.
....(I)
....(II)
....(III)
Where, v = velocity
t = time
a = acceleration
s = position , distance