Answer:
The wave is traveling in the +x direction.
Explanation:
The equation of a wave is given by the formula as :

Here,
A is the amplitude of wave
is the phase of wave
is the angular frequency of the wave
We need to find the correct statement out of given options. The given equation can be rewritten as :

Here, the propagation constant is negative. So, the wave is moving in +x direction. Hence, the correct option is (a).
Answer:

Explanation:
The energy of a photon is given by:

where
is the Planck constant
is the frequency of the photon
Substituting the numbers into the equation, we find:

When an elevator is accelerating downward, the normal force is equal to mg-ma (hence you feel a little lighter when accelerating downwards)
Therefore, the upward force of the elevator floor on the person must be less than 750N
Force is a vector quantity
so pulling from opposite side will be negative
so
750+(-500)= 250N
C is the right answer
becauseause the man on the right applies greater force.