All categories

2 years ago

In a simple machine, what does it mean :i) If efficiency is said to be 65%.

2 answers:

8 0

It is an real machine because if efficiency is below100% it is real machine but if efficiency is 100% it is an ideal machine

hichkok12 [17]2 years ago

7 0

This machine is has an efficiency of 65% which means the machines is ok not that efficient

You might be interested in

A photon of wavelength 2.78 pm scatters at an angle of 147° from an initially stationary, unbound electron. What is the de Brogl

Elena-2011 [213]

Answer:

2.07 pm

Explanation:

The problem given here is the very well known Compton effect which is expressed as

$\lambda^{'}-\lambda=\frac{h}{m_e c}(1-cos\theta)$

here, $\lambda$ is the initial photon wavelength, $\lambda^{'}$ is the scattered photon wavelength, h is he Planck's constant, $m_e$ is the free electron mass, c is the velocity of light, $\theta$ is the angle of scattering.

Given that, the scattering angle is, $\theta=147^{\circ}$

Putting the respective values, we get

$\lambda^{'}-\lambda=\frac{6.626\times 10^{-34} }{9.11\times 10^{-31}\times 3\times 10^{8} } (1-cos147^\circ ) m\\\lambda^{'}-\lambda=2.42\times 10^{-12} (1-cos147^\circ ) m.\\\lambda^{'}-\lambda=2.42(1-cos147^\circ ) p.m.\\\lambda^{'}-\lambda=4.45 p.m.$

Here, the photon's incident wavelength is $\lamda=2.78pm$

Therefore,

$\lambda^{'}=2.78+4.45=7.23 pm$

From the conservation of momentum,

$\vec{P_\lambda}=\vec{P_{\lambda^{'}}}+\vec{P_e}$

where, $\vec{P_\lambda}$ is the initial photon momentum, $\vec{P_{\lambda^{'}}}$ is the final photon momentum and $\vec{P_e}$ is the scattered electron momentum.

Expanding the vector sum, we get

$P^2_{e}=P^2_{\lambda}+P^2_{\lambda^{'}}-2P_\lambda P_{\lambda^{'}}cos\theta$

Now expressing the momentum in terms of De-Broglie wavelength

$P=h/\lambda,$

and putting it in the above equation we get,

$\lambda_{e}=\frac{\lambda \lambda^{'}}{\sqrt{\lambda^{2}+\lambda^{2}_{'}-2\lambda \lambda^{'} cos\theta}}$

Therefore,

$\lambda_{e}=\frac{2.78\times 7.23}{\sqrt{2.78^{2}+7.23^{2}-2\times 2.78\times 7.23\times cos147^\circ }} pm\\\lambda_{e}=\frac{20.0994}{9.68} = 2.07 pm$

This is the de Broglie wavelength of the electron after scattering.

6 0

3 years ago

Phân biệt các đặc điểm khác nhau giữa chất rắn, chất lỏng

vitfil [10]

Answer:

şen çal kapimi turkish drama

6 0

2 years ago

An object accelerates in a direction that is always perpendicular to its motion.

anzhelika [568]

The object will not be able to accelerate perpendicular to direction of motion

7 0

3 years ago

The fluid inside the hydraulic jack has a pressure of 30,000 Pa. If the surface of

aleksley [76]

Explanation:

p = F /A

F = P×A

F = 30,000 Pa / 0.1 m²

F = 300,000 N

5 0

2 years ago

Showing results for a 4 olm and 8 ohm resistor are connected in series. The current through the 4 olm resistor is 2 amps. What i

kirill115 [55]

Answer:

Let R1= resistance of 4ohms

R2= resistance of 8ohms

Equivalent resistance R will be

R=R1 + R2

=> 4+8=12ohms

The current through the two resistors will be the same since they are connected in series. Notwithstanding, the voltage will drop to appreciate the change.

Explanation:

7 0

2 years ago