Are ultrasound waves high energy waves or low energy waves?

An archer pulls a bow string 0.5 m. If the spring constant is 16,000 N/m, what is the energy stored in the bow string?

mars1129 [50]

2000J

Explanation:

Given parameters:

Extension = 0.5m

Spring constant = 16000N/m

Unknown:

Energy stored in the bow string = ?

Solution:

The energy stored in a bow string is an elastic potential energy.

It can be calculated using the expression below;

Elastic energy = $\frac{1}{2}$ K e²

Where k is the spring constant

e is the extension

Input the parameters;

Elastic energy = $\frac{1}{2}$ K e²

= $\frac{1}{2}$ x 16000 x 0.5²

= 2000J

learn more:

Potential energy brainly.com/question/10770261

#learnwithBrainly

3 0

3 years ago

Two boys are at the top of a waterslide at Seven Peaks Water Park. One boy (boy A) slips off the top of the tower and falls unob

Illusion [34]

Answer: boy B, same

Explanation:

Given

One boy trips off the waterslide while the other starts sliding down

As there is no horizontal velocity, both boys have to travel the same vertical distance.

Their starting vertical velocity is zero and they need to travel the same vertical distance. Therefore, both boys splash water with the same velocity.

The time taken by boy B is more than boy A as boy B will travel some horizontal distance due to slide which will increase its time to reach the bottom.

4 0

2 years ago

A box of books has _______inertia than a box of cotton balls.

White raven [17]

Talking about a quantity of inertia is exactly the same as talking about a quantity of mass. So, if the boxes are anywhere near the same size, then the box of books has <u><em>more</em></u> inertia than the box of cotton balls, because books have more mass than an identical volume of cotton.

4 0

3 years ago

Read 2 more answers

A farmer lifts his hay bales into the top loft of his barn by walking his horse forward with a constant velocity of 1 ft/s. Dete

Lesechka [4]

Answer:

The velocity of the hay bale is - 0.5 ft/s and the acceleration is $6.25\times 10^{- 3} ft/s^{2}$

Solution:

As per the question:

Constant velocity of the horse in the horizontal, $v_{x} = 1 ft/s$

Distance of the horse on the horizontal axis, x = 10 ft

Vertical distance, y = 20 ft

Now,

Apply Pythagoras theorem to find the length:

$20^{2} + 10^{2} = l^{2}$

$l^{2}= 500$

Now,

$x^{2} + y^{2} = 500$ (1)

Differentiating equation (1) w.r.t 't':

$2x\frac{dx}{dt} + 2y\frac{dy}{dt} = 0$

$x\frac{dx}{dt} = - y\frac{dy}{dt}$

where

$\frac{dx}{dt}$ = Rate of change of displacement along the horizontal

$\frac{dy}{dt}$ = Rate of change of displacement along the vertical

$v_{x}$ = velocity along the x-axis.

$v_{y}$ = velocity along the y-axis

$xv_{x} = -yv_{y}$

$v_{y} = - 10\times \frac{1}{20} = - 0.5 ft/s$

$|v_{y}| = 0.5\ ft/s$

Acceleration of the hay bale is given by the kinematic equation:

$v_{y}^{2} = u_{y} + 2ay$

$(-0.5)^{2} =0 + 2ay$

$0.25 = 2ay$

$\frac{0.25}{2y} = a$

$a = \frac{0.25}{2\times 20} = 6.25\times 10^{- 3} ft/s^{2}$

7 0

3 years ago

A swinging pendulum has a total energy of <img src="https://tex.z-dn.net/?f=E_i" id="TexFormula1" title="E_i" alt="E_i" align="a

Zolol [24]

Answer:

$\frac{E_{2}}{E_{1}} \approx 1 -\frac{3\theta}{1-\theta}$ (for small oscillations)

Explanation:

The total energy of the pendulum is equal to:

$E_{1} = m\cdot g \cdot (1-\cos \theta)\cdot L$

For small oscillations, the equation can be re-arranged into the following form:

$E_{1} \approx m\cdot g \cdot (1-\theta) \cdot L$

Where:

$\theta = \frac{A}{L^{2}}$ , measured in radians.

If the amplitude of pendulum oscillations is increase by a factor of 4, the angle of oscillation is $4\theta$ and the total energy of the pendulum is:

$E_{2} \approx m\cdot g \cdot (1-4\theta)\cdot L$

The factor of change is:

$\frac{E_{2}}{E_{1}} \approx \frac{1 - 4\theta}{1-\theta}$

$\frac{E_{2}}{E_{1}} \approx 1 -\frac{3\theta}{1-\theta}$

3 0

3 years ago