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andreev551 [17]
3 years ago
7

An automobile accelerates uniformly from a speed of 60 km/hr (16.67 m/s) to a speed of 80 km/hr (22.2 m/s) in 5 s. Determine the

acceleration of the car and the distance traveled in this 5 sec interval.
Physics
1 answer:
monitta3 years ago
7 0

Answer:

The acceleration is 1.106\ m/s^2 and the distance covered is 97.17 m.

Explanation:

Given that,

Initial speed of an automobile, u = 60 km/hr = 16.67 m/s

Final speed of an automobile, v = 80 km/hr = 22.2 m/s

Time, t = 5 s

We need to find the acceleration of the car and the distance traveled in this 5 sec interval.  Let a is the acceleration. Using the definition of acceleration as :

a=\dfrac{v-u}{t}\\\\a=\dfrac{22.2-16.67}{5}\\\\a=1.106\ m/s^2

Let d is the distance covered. Using the third equation of motion to find it as follows :

v^2-u^2=2as\\\\s=\dfrac{v^2-u^2}{2a}\\\\s=\dfrac{(22.2)^2-(16.67)^2}{2\times 1.106}\\\\s=97.17\ m

So, the acceleration is 1.106\ m/s^2 and the distance covered is 97.17 m.

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Answer:

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Explanation:

A. To calculate the energy of the photon emitted you use the following formula:

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You first convert the energy from eV to J:

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A discharge lamp rated at 25 W (1 W = 1 J/s) emits yellow light of wavelength 580 nm. How many photons of yellow light does the
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Answer:

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given information:

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time, t = 1 s

to calculate the number of photon(N), we use the following equation

N = λPt/hc

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So,

N = λPt/hc

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see answer.

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