Ask question

Ask question

All categories

3 years ago

5

Calculate the angle θ between the radius-vector of the point and the positive x axis (measured counterclockwise from the positiv

e x axis, within the limits of −180◦ to +180◦ ). Answer in units of ◦

1 answer:

Y_Kistochka [10]3 years ago

6 0

The point obviously is in the 3rs quadrant

So

စ= tan^-1( y/x)-180

စ= -89.7°

You might be interested in

A spring gun is made by compressing a spring in a tube and then latching the spring at the compressed position. A 4.97-g pellet

dimaraw [331]

Answer:

$v = 2.8898 \frac{m}{s}$

Explanation:

This is a problem easily solve using energy conservation. As there are no non-conservative forces, we know that the energy is conserved.

When the spring is compressed downward, the spring has elastic potential energy. When the spring is relaxed, there is no elastic potential energy, but the pellet will have gained gravitational potential energy and kinetic energy. Lets see what are the terms for each of this.

<h3>Elastic potential energy</h3>

We know that a spring following Hooke's Law has a elastic potential energy:

$E_{ep} = \frac{1}{2} k (\Delta x)^2$

where $\Delta x$ is the displacement from the relaxed length and k is the spring's constant.

To obtain the spring's constant, we know that Hooke's law states that the force made by the spring is :

$\vec{F} = - k \Delta \vec{x}$

as we need 9.12 N to compress 4.60 cm, this means:

$k = \frac{9.12 \ N}{4.6 \ 10^{-2} \ m}$

$k = 198.26 \ \frac{ N}{m}$

So, the elastic energy of the compressed spring is:

$E_{ep} = \frac{1}{2} 198.26 \ \frac{ N}{m} (4.6 \ 10^{-2} \ m)^2$

$E_{ep} = 0.209759 \ Joules$

And when the spring is relaxed, the elastic potential energy will be zero.

<h3>Gravitational potential energy</h3>

To see how much gravitational potential energy will the pellet win, we can use

$\Delta E_{gp} = m g \Delta h$

where m is the mass of the pellet, g is the acceleration due to gravity and \Delta h is the difference in height.

Taking all this together, the gravitational potential energy when the spring is relaxed will be:

$\Delta E_{gp} = 4.97 \ 10^{-3} kg \ 9.8 \frac{m}{s^2} 4.6 \ 10^{-2} m$

$\Delta E_{gp} = 0.00224 \ Joules$

<h3>Kinetic Energy</h3>

We know that the kinetic energy for a mass m moving at speed v is:

$E_k = \frac{1}{2} m v^2$

so, for the pellet will be

$E_k = \frac{1}{2} \ 4.97 \ 10^{-3} kg \ v^2$

<h3>All together</h3>

By conservation of energy, we know:

$E_{ep} = \Delta E_{gp} + E_k$

$0.209759 \ Joules = 0.00224 \ Joules + \frac{1}{2} \ 4.97 \ 10^{-3} kg \ v^2$

So

$\frac{1}{2} \ 4.97 \ 10^{-3} kg \ v^2 = 0.209759 \ Joules - 0.00224 \ Joules$

$\frac{1}{2} \ 4.97 \ 10^{-3} kg \ v^2 = 0.207519 \ Joules$

$v = \sqrt{ \frac{ 0.207519 \ Joules}{ \frac{1}{2} \ 4.97 \ 10^{-3} kg } }$

$v = 2.8898 \frac{m}{s}$

7 0

3 years ago

How much work is done in holding a 20 N sack of potatoes while waiting in line at the

Yuki888 [10]

Answer: A

Explanation:

honestly, it sounded the best

8 0

2 years ago

In an arcade game, a 0.126 kg disk is shot across a frictionless horizontal surface by compressing it against a spring and relea

bearhunter [10]

Answer:

4.156 m/s

Explanation:

See attachment

4 0

3 years ago

Х<br> Help<br> Close<br> Pre-video question: What type of cell division produces sperm and<br> ova?

vovangra [49]

Answer:

HI THERE

Explanation:

MEIOSIS produces sperm and ova

thank you

I am also reading this chapter

it will come in my exams

8 0

2 years ago

Read 2 more answers

Which of newton's three laws is the hardest to describe or explain when viewing common occurrences?

choli [55]

Newton's second law is the hardest to describe as it is about momentum (F = ma), and a lot of people don't know the concept of momentum.

Newton's first law of motion:- every object moves in a straight line unless acted upon by a force.

Newton's 2nd law of motion:-the acceleration of an object is directly proportional to the net force exerted and inversely proportional to the item's mass. Newton's 2nd law is a quantitative description of the changes that a force can produce on the motion of a body. It states that the time rate of change of the momentum of a body is equal in both magnitude and direction to the force imposed on it.

Newton's 3rd law of motion:- For every action, there's an equal and opposite reaction.

learn more about Newton's first law of motion here brainly.com/question/10454047

#SPJ4

8 0

2 years ago