<span>C. waves can only interfere destructively. </span>
by the concept of momentum conservation we can say
if net force on a system of mass is ZERO then its momentum will remain conserved
Here a ball is projected upwards so if we take Ball + Earth as a system then total momentum of the system will remain conserved
Initially when ball is on the surface of earth the system has zero momentum and hence we can say after throwing the ball momentum of earth + ball must be zero
now using same equation we can say


given that



from above equation velocity of earth will be



so above will be the recoil speed of earth
I really don’t know I just need some points to help me though this test I’m very sorry
The dimension of K is M/ T^2
according to the question T=2π square root ofm/k here 2 pi is constant so
T= root of m /k and root of k = root of m/ T now by squaring on both the sides we get the answer k= M/ T^2
complete question :
A spring is hanging down from the ceiling, and an object of mass m is attached to the free end. The object is pulled down, thereby stretching the spring, and then released. The object oscillates up and down, and the time T required for one complete up-and-down oscillation is given by the equation T=√2πm/k, where k is known as the spring constant. What must be the dimension of k for this equation to be dimensionally correct?
To learn more about dimension:
brainly.com/question/13314350
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