Answer:
5000 kg/m^3
Explanation:
Here. we are asked to calculate the density of the rock specimen.
we proceed as follows;
mass of water displaced is calculated by finding the difference between the actual and apparent masses
This has a value of 0.45kg - 0.36kg = 0.09kg
The rock and water that is displaced have exactly the same volume and thus their densities is the same. This makes the ratio of their masses to be the same
Ratio of masses is
0.45 / 0.09 = 5.0
Here we can see that the mass of the rock is five times the mass of the water so it must be five times denser
Thus, since the density of water is 1000 kg/m^3 , the density of rock is 5000 kg/m^3
Final speed after collision with the wall
before collision the speed of ball initially
time taken for the collision
now as per the formula of acceleration we know that
now plug in all values in it
so acceleration is - 5 m/s/s for above situation
Answer:
Less than 1 m
Explanation:
When objects are getting closer to each other there is a slight change in the wavelength that is being transmitted by either objects. This is known as the blue shift of waves. Here, the wavelength reduces.
In the opposite case the when objects are getting farther from each other there is a slight change in the wavelength that is being transmitted by either objects. This is known as the red shift. Here, the wavelength increases.
In this case the spaceship is getting close to Earth hence the wavelength will be lower than 1 m.
Answer:
25.33 rpm
Explanation:
M = 100 kg
m1 = 22 kg
m2 = 28 kg
m3 = 33 kg
r = 1.60 m
f = 20 rpm
Let the new angular speed in rpm is f'.
According to the law of conservation of angular momentum, when no external torque is applied, then the angular momentum of the system remains constant.
Initial angular momentum = final angular momentum
(1/2 x M x r^2 + m1 x r^2 + m2 x r^2 + m3 x r^2) x ω =
(1/2 x M x r^2 + m1 x r^2 + m3 x r^2 ) x ω'
(1/2 M + m1 + m2 + m3) x 2 x π x f = (1/2 M + m1 + m3) x 2 x π x f'
( 1/2 x 100 + 22 + 28 + 33) x 20 = (1/2 x 100 + 22 + 33) x f'
2660 = 105 x f'
f' = 25.33 rpm
