Answer:
A) Newton’s 1st Law
Explanation:
W=mg
m = W/g = 390N/ 9.8 m/s^2 = 39.8 kg
some people round g to 10 m/s^2 and this will give answer of 39 kg, which is wrong
Answer:
They are formed on or near the Earth’s surface from the compression of ocean sediments or other processes.
Explanation:
Nope. It means that the density of the object is less than the density of the water it's in, making it float. Conversely, if the density of an object is greater than the density of the water it's in, then the object will sink. :)
Answer:
the moment of inertia of the merry go round is 38.04 kg.m²
Explanation:
We are given;
Initial angular velocity; ω_1 = 37 rpm
Final angular velocity; ω_2 = 19 rpm
mass of child; m = 15.5 kg
distance from the centre; r = 1.55 m
Now, let the moment of inertia of the merry go round be I.
Using the principle of conservation of angular momentum, we have;
I_1 = I_2
Thus,
Iω_1 = I'ω_2
where I' is the moment of inertia of the merry go round and child which is given as I' = mr²
Thus,
I x 37 = ( I + mr²)19
37I = ( I + (15.5 x 1.55²))19
37I = 19I + 684.7125
37I - 19 I = 684.7125
18I = 684.7125
I = 684.7125/18
I = 38.04 kg.m²
Thus, the moment of inertia of the merry go round is 38.04 kg.m²