How do you determine the density of an empty plastic jug?

A student throws a small rock straight upwards. The rock rises to its highest point and then falls back down. How does the speed

Vladimir [108]

Answer:

we assume that it starts with a velocity of 10m/s. At 2m height above ground level, its velocity decreases at 3m above ground level

for its way down the velocity at 3m on its way down is more than its velocity at 2m on its way down.

Explanation:

A student throws a small rock straight upwards. The rock rises to its highest point and then falls back down. How does the speed of the rock at 2m on the way down compare with its speed at 2m on the way up?

It decreases in speed on its way down and increases in speed on its way down.

it decreases in speed on its way up because the the vertical motion is against the earths gravitational pull on an object to the earth's center

.It increases in speed on his way down because its under the influence of gravity

from newton's equation of motion we can check by

using V^2=u^2+2as

we assume that it starts with a velocity of 10m/s. At 2m height above ground level, its velocity decreases at 3m above ground level

for its way down the velocity at 3m on its way down is more than its velocity at 2m on its way down.

5 0

3 years ago

Please answer help me

Andrews [41]

I believe the answer is x

7 0

3 years ago

How much work is required to stop an electron (m = 9.11 \times 10^ - 31 kg) which is moving with a speed of 2.10

Karo-lina-s [1.5K]

Answer:

$-2.00876\times 10^{-18}\ J$

Explanation:

v = Speed of electron = $2.1\times 10^6\ m/s$ (generally the order of magnitude is 6)

m = Mass of electron = $9.11\times 10^{-31}\ kg$

Work done would be done by

$W=K_i-K_f\\\Rightarrow W=0-\dfrac{1}{2}mv^2\\\Rightarrow W=0-\dfrac{1}{2}\times 9.11\times 10^{-31}\times (2.1\times 10^6)^2\\\Rightarrow W=-2.00876\times 10^{-18}\ J$

The work required to stop the electron is $-2.00876\times 10^{-18}\ J$

6 0

3 years ago

Problem set 3 » (8) river swimming a swimmer heads directly across a river, swimming at her maximum speed of 1.30 m/s relative t

jasenka [17]

Velocity of swimmer across river = 1.30 m/s

Distance arrived downstream = 48 m

Width of river = 64 m

Time taken to cross river = $\frac{Width of river}{Velocity across river}$

= $\frac{64}{1.30} =49.23 s$

Speed of river current = $\frac{Distance arrived downstream}{Time taken to cross river}$

= $\frac{48}{49.23} = 0.975 m/s$

So, the river is flowing at a speed 0.975 m/s.

5 0

3 years ago

The 300 m diameter Arecibo radio telescope is observing the Andromeda galaxy at a wavelength of 29 cm. show answer No Attempt 50

jekas [21]

Answer:

The angle between two just-resolvable stars for the Arecibo telescope is $1.179x10^{-3}rad$ .

Explanation:

The resulting image in a telescope obtained from an object is a diffraction pattern.

That diffraction pattern is obtained because the light encounters different obstacles on its path inside the telescope (interact with the walls and edges of the instrument).

The diffraction pattern is composed by a central disk, called Airy disk, and diffraction rings.

The angular resolution is defined as the minimal separation at which two sources can be resolved one for another, or in other words, when the distance between the two diffraction patterns maxima is greater than the radius of the Airy disk.

The angular resolution can be determined in an analytical way by means of the Rayleigh criterion.

$\theta = 1.22\frac{\lambda}{D}$ (1)