The energy of a photon is given by:
where h is the Planck constant and f is the photon frequency.
We know the energy of the photon,
, so we can rearrange the equation to calculate the frequency of the photon:
And now we can use the following relationship between frequency f, wavelength
and speed of light c to find the wavelength of the photon:
d = distance traveled by her on her bicycle on a long flat road = 24 kilometer
t = time taken by her to travel distance "d" on her bicycle on a long flat road = 1.2 hours
v = average speed of vivian = ?
we know that average speed is given as
v = d/t
inserting the values in the above formula
v = 24 kilometer / 1.2 hour
v = 20 kilometer/hour
hence the correct choice is
C) 20 km/h
Answer:
16.935 N
Explanation:
In order to make the box start moving, the level force applied on the box (F) must be greater than the force of static friction that keeps the box at rest, which is equal to
where
is the coefficient of static friction
(mg) = 30 N is the weight of the box
Therefore, the condition for F must be:
So, the applied force must be greater than this value.
Answer:
47.4 m
Explanation:
When an object is thrown upward, it rises up, it reaches its maximum height, and then it goes down. The time at which it reaches its maximum height is half the total time of flight.
In this case, the time of flight is 6.22 s, so the time the ball takes to reach the maximum height is
Now we consider only the downward motion of the ball: it is a free fall motion, so we can find the vertical displacement by using the suvat equation
where
s is the vertical displacement
u = 0 is the initial velocity
t = 3.11 s is the time
is the acceleration of gravity (taking downward as positive direction)
Solving the formula, we find
Answer:
Magnitude of y-component=7 units
Direction= angle of vector A with x-axis= 
Explanation:
Explained solution is in the picture attached
