TheThe relative velocity of Deigo will be 27km/h .
<h3>What is relative Velocity? </h3>
The relative velocity is the velocity of an object with respect to another observer. It is the time rate of relative position of one object with respect to another object .
Vab = Va-Vb
Where a is object and b is observer .
We have given here the velocity of ball 20km/ h
and the another velocity is 7km/ h
Let us assume that Diego is also moving in the direction where ball is moving so the relative velocity will be
V = 20+7=27km/ h
When both observer and object is moving in same direction than there sum of velocity will be relative velocity ,if they are moving opposite than subtraction.
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Answer:
<em>600N.</em>
Explanation:
From the question, we are to calculate the net force acting on the car.
According to Newton's second law of motion:
F = ma
m is the mass of the car
a is the acceleration = change in velocity/Time
a = v-u/t
F = m(v-u)/t
v is the final velocity = 30m/s
u is the initial velocity = 20m/s
t is the time = 5secs
m = 300kg
Get the net force:
Recall that: F = m(v-u)/t
F = 300(30-20)/5
F = 60(30-20)
F = 60(10)
<em>F = 600N</em>
<em>Hence the net force acting on the car is 600N.</em>
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1.549×10-19lJ is the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from =7 to =1.
The equation E= hcE =hc, where h is Planck's constant and c is the speed of light, describes the inverse relationship between a photon's energy (E) and the wavelength of light ().
The Rydberg formula is used to determine the energy change.
Rydberg's original formula used wavelengths, but we may rewrite it using units of energy instead. The result is the following.
aaΔE=R(1n2f−1n2i) aa
were
2.17810-18lJ is the Rydberg constant.
The initial and ultimate energy levels are ni and nf.
As a change of pace from
n=5 to n=3 gives us
ΔE
=2.178×10-18lJ (132−152)
=2.178×10-18lJ (19−125)
=2.178×10-18lJ×25 - 9/25×9
=2.178×10-18lJ×16/225
=1.549×10-19lJ
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