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3 years ago

PLEASE HELP ME WITH THIS ONE QUESTION

Physics

1 answer:

melamori03 [73]3 years ago

3 0

Explanation:

First, we convert the energy from eV to Joules:

$2.90\:\text{eV}×\left(\dfrac{1.6×10{-19}\:J}{1\:\text{eV}} \right)$

$= 4.64×10^{-19}\:\text{eV}$

We know from definition that

$E=h\nu = \dfrac{hc}{\lambda}$

so the wavelength of the photon is

$\lambda = \dfrac{hc}{E} = 4.28×10^8\:\text{m}$

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A test of the prototype of a new automobile shows that the minimum distance for a controlled stop from 95 km/h to zero is 55 m.

iris [78.8K]

Answer:

-0.64525g

Explanation:

t = Time taken for the car to stop

u = Initial velocity = 95 km/h

v = Final velocity = 0 km/h

s = Displacement

a = Acceleration

Equation of motion

$v^2-u^2=2as\\\Rightarrow a=\frac{v^2-u^2}{2s}\\\Rightarrow a=\frac{0^2-95^2}{2\times 0.055}\\\Rightarrow a=-82045.45\ km/h^2$

Converting to m/s²

$a=82045.45=\frac{82045.45\times 1000}{3600\times 3600}=-6.33\ m/s^2$

g = Acceleration due to gravity = 9.81 m/s²

Dividing both the accelerations, we get

$\frac{a}{g}=\frac{-6.33}{9.81}=-0.64525\\\Rightarrow a=-0.64525g$

Hence, acceleration of the car is -0.64525g

8 0

3 years ago

A small electronic device is rated at 0.16 W when connected to 115 V. What is the resistance of this device?

Ierofanga [76]

Answer:

150156.25 Ω

Explanation:

Resistance: This can be defined as the opposition to the flow of electric current in a circuit. The S.I unit of resistance is Ohm's (Ω)

The expression for resistance is given as

P = V²/R................ equation 1

Where P = power, V = Voltage, R = Resistance.

Making R the subject of the equation,

R = V²/P.................. Equation 2

Given: V = 115 V , P = 0.16 W.

Substitute into equation 2

R = 155²/0.16

R = 150156.25 Ω

Hence,

The resistance = 150156.25 Ω

8 0

3 years ago

Read 2 more answers

Scientists use laser range-finding to measure the distance to the moon with great accuracy. A brief laser pulse is fired at the

Fofino [41]

Answer:

d = 2,042 10-3 m

Explanation:

The laser diffracts in the circular slit, so the process equation is

d sin θ= m λ

The first diffraction minimum occurs for m = 1

We can use trigonometry in the mirror

tan θ = Y / L

Where L is the distance from the Moon to Earth

Since the angle is extremely small

tan θ = sin θ / cos θ

Cos θ = 1

tant θ = sin θ = y / L

We replace

d y / L = λ

d = λ L / y

Let's calculate

d = 532 10⁻⁹ 3.84 10⁶/1 10³

d = 2,042 10-3 m

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3 years ago

Light is a form of what

mart [117]

Light is a form of energy.
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As you learned in Part B, a non-burning helium core surrounded by a shell of hydrogen-burning gas characterizes the subgiant sta

Gennadij [26K]

Answer:

E- The star becomes a red giant (LATEST STAGE)

F- The surface of the star becomes brighter and cooler

C- Pressure from the star's hydrogen-burning shell causes the non burning envelope to expand

A- The shell of hydrogen surrounding the star's nonburning helium core ignites.

D- The star's non burning helium core starts to contract and heat up

B- Pressure in the star's core decreases (EARLIEST STAGE)

(A star moves away from the main sequence once its core runs out of hydrogen to fuse into helium. The energy once supplied by hydrogen burning reduces and the core starts to compress under the force of gravity. This contraction allows the core and surrounding layers to heat up. Finally, the hydrogen shell around the core becomes hot enough to ignite hydrogen burning.

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3 years ago