The correct choice is
D. 22 Hz and 42 Hz.
In fact, the beat frequency is given by the difference between the frequencies of the two waves:
In this problem, the beat frequency is , therefore the only pair of frequencies that gives a difference equal to 20 Hz is
D. 22 Hz and 42 Hz.
Answer:
19.3m/s
Explanation:
Use third equation of motion
where v is the velocity at halfway, u is the initial velocity, g is gravity (9.81m/s^2) and h is the height at which you'd want to find the velocity
insert values to get answer
Answer:
The change in potential energy is
Explanation:
From the question we are told that
The magnitude of the uniform electric field is
The distance traveled by the electron is
Generally the force on this electron is mathematically represented as
Where F is the force and q is the charge on the electron which is a constant value of
Thus
Generally the work energy theorem can be mathematically represented as
Where W is the workdone on the electron by the Electric field and is the change in kinetic energy
Also workdone on the electron can also be represented as
Where considering that the movement of the electron is along the x-axis
So
substituting values
Now From the law of energy conservation
Where is the change in potential energy
Thus
The initial velocity of the cat is 56.6 m/s
Explanation:
The motion of the cat is a projectile motion, consisting of:
- a uniform horizontal motion with constant velocity
- a vertical accelerated motion with constant acceleration (free fall)
We start by analyzing the vertical motion, to find the time it takes for the cat to reach the ground. We use the following suvat equation:
where we have (choosing downard as positive direction)
s = 125 m is the vertical displacement of the cat
u = 0 is the initial vertical velocity
t is the time taken to reach the ground
is the acceleration of gravity
Solving for t, we find
Now we can analzye the horizontal motion. Since the motion is uniform and the horizontal velocity is constant, it is given by
where
d = 286 m is the horizontal distance travelled
t = 5.05 s is the time taken
Solving the equation,
Learn more about projectile motion:
#LearnwithBrainly