Answer:
DETAILS IN THE QUESTION INSUFFICIENT TO ANSWER
Explanation:
Assuming the liquid to be water ,
the density
of water is :
Buoyant force exerted by a liquid on an object with
of it's volume immersed is :

where ,
is the buoyant force
is the density of the liquid
is the acceleration due to gravity
Thus at equilibrium:

from these , we get the density of brass to be 
which is not possible
Answer:
a = -4/5 m/s^2
Explanation:
Acceleration = change in velocity / time
change in velocity = final velocity - initial velocity
a = (20 m/s - 60 m/s) / 50 s
a = -40 m/s / 50 s
a = -4/5 m/s^2
hope this helps! <3
A. very small objects behave like like particles.
Consider the upward direction of motion as positive and downward direction of motion as negative.
a = acceleration due to gravity in downward direction = - 9.8 
v₀ = initial velocity of rock in upward direction = ?
v = final velocity of rock at the highest point = 0 
t = time to reach the maximum height = 4.2 sec
Using the kinematics equation
v = v₀ + a t
inserting the values
0 = v₀ + (- 9.8) (4.2)
v₀ = 41.2 
If a force always acts perpendicular to an object's direction of motion, that force cannot change the object's kinetic energy. It is a true statement .
Kinetic energy is the energy that an object possesses due to its motion. It is basically the energy of mass in motion. Kinetic energy can never be negative and it is a scalar quantity i.e. it provides only the magnitude and not the direction.
According to law of conservation of mechanical energy change in potential energy is equal and opposite to the change in the kinetic energy.
According to the principle of conservation of mechanical energy, The total mechanical energy of a system is conserved i.e., the energy can neither be created nor be destroyed; it can only be internally converted from one form to another if the forces doing work on the system are conservative in nature.
since, potential energy is stored in the form of work done
Work done = Fs cos (theta)
If force always acts perpendicular to an object's direction of motion
theta = 90 °
cos (90 ) = 0
Work done = 0
since , there is no work done , hence kinetic energy will not change
To learn more about kinetic energy here
brainly.com/question/12669551
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