If you push on a wall with a force of 200 N, with what force does the wall push back?

For which one of the following situations will the path length equal the magnitude of the displacement? a A ball on the end of a

PSYCHO15rus [73]

Answer:

d A ball is rolling down an inclined plane.

Explanation:

When path length is equal to the displacement

then we can say that the motion of the object must be in straight line so that the distance and displacement must be same

SO here we can say

a A ball on the end of a string is moving in a vertical circle.

In circular path distance and displacement is not same

b A toy train is traveling around a circular track.

In circular path distance and displacement is not same

c A train travels 5 miles east before it stops. It then travels 2 miles west.

Net displacement is 3 miles East while distance is 7 miles

d A ball is rolling down an inclined plane.

Here its motion is in straight line so we can say that path length and displacement will be same

e A ball rises and falls after being thrown straight up from the earth's surface.

In this type of to and fro motion path length is not same as displacement

7 0

3 years ago

2

Xelga [282]

Answer:

About 7.67 m/s.

Explanation:

Mechanical energy is always conserved. Hence:

$\displaystyle \begin{aligned} E_i & = E_f \\ \\ U_i + K_i &= U_f + K_f\end{aligned}$

Where U is potential energy and K is kinetic energy.

Let the bottom of the slide be where potential energy equals zero. As a result, the final potential energy is zero. Additionally, because the child starts from rest, the initial kinetic energy is zero. Thus:

$\displaystyle U_i = K_f$

Substitute and solve for final velocity:
$\displaystyle \begin{aligned} mgh_i &= \frac{1}{2}mv_f^2 \\ \\ 2gh_i &= v^2_f \\ \\ v_f &= \sqrt{2gh_i} \\ \\ & =\sqrt{2(9.8\text{ m/s$^2$})(3.00\text{ m})} \\ \\ & \approx 7.67\text{ m/s} \end{aligned}$

In conclusion, the child's speed at the bottom of the slide is about 7.67 m/s.

8 0

1 year ago

As outlaws escape in their getaway ear, which goes 3/4 c, the police officer fires a bullet from a pursuit ear, which only goes

Mariulka [41]

Answer:

a) Bullet will hit

b) Bullets will not hit

Explanation:

Given:

The velocity of the bullet, u = $\frac{1}{3}c$ in the rest frame of the bullet pursuit car

The velocity of the original frame of reference, v = $-\frac{1}{2}c$ with respect to the pursuit car.

Now, according to the Galileo

the velocity of the bullet in the original frame of reference (u') will be

u' = u - v

on substituting the values we get

u' = $\frac{1}{3}c-(-\frac{1}{2}c)$

or

u' = $\frac{1}{3}c+\frac{1}{2}c$

or

u' = $\frac{5}{6}c$

since this velocity ( $\frac{5}{6}c$ ) is greater than the ( $\frac{3}{4}c$ )

hence,

the bullet will hit

Now, according to the Einstein theory

the velocity of the bullet in the original frame of reference (u') will be

$u'=\frac{u-v}{1-\frac{uv}{c^2}}$

on substituting the values we get

$u'=\frac{\frac{1}{3}c-\frac{1}{2}c}{1-\frac{\frac{1}{3}c\times \frac{1}{2}c}{c^2}}$

or

$u'=\frac{\frac{5}{6}c}{1-\frac{1}{6}}$

or

$u'=\frac{5}{7}c$

since,

$u'=\frac{5}{7}c$ is less than ( $\frac{3}{4}c$ ), this means that the bullet will not hit

7 0

3 years ago

Which of the following would be most likely to lead to increased biodiversity

marishachu [46]

C. National Park Planning

Biodiversity - the variety of life in the world or in a particular habitat or ecosystem.

Clear cutting and oil drilling both decrease the variety of life, destroying habitat around them.

Farming decreases biodiversity because it decrease the variety of flora in that area, depending on what crop is planted.

6 0

2 years ago

Can someone help me?!!!!!

kramer

Answer:

Parabola

Explanation:

The motion of a projectile consists of two independent motions:

- A uniform motion along the horizontal (x) direction, with constant velocity $v_x$ . In fact, there are no forces acting along this direction (if we neglect air resistance), so the acceleration is zero and the velocity is constant

- An uniformly accelerated motion along the vertical (y) direction, with constant acceleration $g=9.8 m/s^2$ downward (acceleration due to gravity). This acceleration is due to the force of gravity that pulls the projectile downward.