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2 years ago

A+20 N force acts on a car and at the same time, a -30 N force acts on the

Physics

1 answer:

katovenus [111]2 years ago

5 0

Answer:

-10 N, not balanced

Explanation:

Force is a vector quantity, so in order to find the net force on an object, we must use vector addition rule.

This means that if two forces acting on an object along the same line, we have to choose one direction as positive, and write the two forces with the correct sign.

In this problem, we have two forces acting along a line on the car:

- A first force of

$F_1 = +20 N$

- A second force of

$F_2=-30 N$

Therefore, the net force on the car is:

$\sum F=F_1+F_2=+20 +(-30)=-10 N$

Moreover, the net force on an object is said to be "balanced" if it is zero: in this case, it is not zero, so it is not balanced.

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Answer:

2.07 pm

Explanation:

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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

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

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

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.

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