Answer:
The relative density of the second liquid is 7.
Explanation:
From archimede's principle we know that the force that a liquid exerts on a object equals to the weight of the liquid that the object displaces.
Let us assume that the volume of the object is 'V'
Thus for the liquid in which the block is completely submerged
The buoyant force should be equal to weight of liquid
Mathematically
Thus for the liquid in which the block is 1/7 submerged
The buoyant force should be equal to weight of liquid
Mathematically
Comparing equation 'i' and 'ii' we see that
Since the first liquid is water thus 
Thus the relative density of the second liquid is 7.
Answer:
It's too long questions..
Light travels in waves, and light travels at about 3.0x10^8 m/s. and you call that this the 'speed of light' so your answer possible could be
A. It travels at the speed of light.
I might be wrong so double check.
Answer:
Explanation:
This problem is based on conservation of rotational momentum.
Moment of inertia of rod about its center
= 1/12 m l² , m is mass of the rod and l is its length .
= 1 / 12 x 4.6 x .11²
I = .004638 kg m²
The angular momentum of the bullet about the center of rod = mvr
where m is mass , v is perpendicular component of velocity of bullet and r is distance of point of impact of bullet fro center .
5 x 10⁻³ x v sin60 x .11 x .5 where v is velocity of bullet
According to law of conservation of angular momentum
5 x 10⁻³ x v sin60 x .11 x .5 = ( I + mr²)ω , where ω is angular velocity of bullet rod system and ( I + mr²) is moment of inertia of bullet rod system .
.238 x 10⁻³ v = ( .004638 + 5 x 10⁻³ x .11² x .5² ) x 12
.238 x 10⁻³ v = ( .004638 + .000015125 ) x 12
.238 x 10⁻³ v = 55.8375 x 10⁻³
.238 v = 55.8375
v = 234.6 m /s
Answer:
72Watts
Explanation:
Power = Force * distance/Time
Given the following
Force = 2.4 x 10^2 = 240N
distance = 1.2m
Time = 4.0secs
Substitute
Power = 240*1.2/4
Power = 60 * 1.2
Power = 72watts
Hence the power required to lift the box is 72Watts
