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2 years ago

Express each of the following in ms -1 a) 18kmh-1

1 answer:

3 0

1km=1000m; 1hr=3600secs
1km/hr=1000/3600= 5/18m/sec
To convert km/hr into m/sec, multiply the number by 5 and then divide it by 18.

18kmh-1= 18•5=90
90/18=5
5ms-1

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tino4ka555 [31]

Answer:

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Explanation:

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2 years ago

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MA_775_DIABLO [31]

Answer:

$v_B=3.78\times 10^5\ m/s$

Explanation:

It is given that,

Charge on helium nucleus is 2e and its mass is $6.63\times 10^{-27}\ kg$

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Potential at point A, $V_A=1.5\times 10^3\ V$

Potential at point B, $V_B=4\times 10^3\ V$

We need to find the speed at point B on the circle. It is based on the concept of conservation of energy such that :

increase in kinetic energy = increase in potential×charge

$\dfrac{1}{2}m(v_A^2-v_B^2)=(V_B-V_A)q\\\\\dfrac{1}{2}m(v_A^2-v_B^2)={(4\times 10^3-1.5\times 10^3)}\times 2\times 1.6\times 10^{-19}=8\times 10^{-16}\\\\v_A^2-v_B^2=\dfrac{2\times 8\times 10^{-16}}{6.63\times 10^{-27}}\\\\v_A^2-v_B^2=2.41\times 10^{11}\\\\v_B^2=(6.2\times 10^5)^2-2.41\times 10^{11}\\\\v_B=3.78\times 10^5\ m/s$

So, the speed at point B is $3.78\times 10^5\ m/s$ .

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3 years ago

Calculate the acceleration of an airplane that starts at rest and reaches a speed 45m/s in 9 seconds

sasho [114]

I believe the acceleration would be 5m/s

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3 years ago

Read 2 more answers

Halley's comet orbits the sun roughly once every 76 years. It comes very close to the surface of the Sun on its closest approach

Licemer1 [7]

Answer:

r1 = 5*10^10 m , r2 = 6*10^12 m

v1 = 9*10^4 m/s

From conservation of energy

K1 +U1 = K2 +U2

0.5mv1^2 - GMm/r1 = 0.5mv2^2 - GMm/r2

0.5v1^2 - GM/r1 = 0.5v2^2 - GM/r2

M is mass of sun = 1.98*10^30 kg

G = 6.67*10^-11 N.m^2/kg^2

0.5*(9*10^4)^2 - (6.67*10^-11*1.98*10^30/(5*10^10)) = 0.5v2^2 - (6.67*10^-11*1.98*10^30/(6*10^12))

v2 = 5.35*10^4 m/s

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3 years ago

A 76-W incandescent light bulb operates at 120 V. How many electrons and coulombs flow through the bulb in one day?

Tema [17]

Answer:

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Explanation:

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3 years ago

Express each of the following in ms -1 a) 18kmh-1​

Express each of the following in ms -1 a) 18kmh-1