Select the correct answer.

Four students made a graphic organizer describing the parts of the atom.

Nikitich [7]

Answer:

I believe the answer is D.

Explanation:

Protons are found inside the nucleus so are neutrons. Electrons are found outside the nucleus.

8 0

3 years ago

Read 2 more answers

A skater extends her arms, holding a 2 kg mass in each hand. She is rotating about a vertical axis at a given rate. She brings h

Usimov [2.4K]

Explanation:

It is known that relation between torque and angular acceleration is as follows.

$\tau = I \times \alpha$

and, I = $\sum mr^{2}$

So, $I_{1} = 2 kg \times (1 m)^{2} + 2 kg \times (1 m)^{2}$

= 4 $kg m^{2}$

$\tau_{1} = 4 kg m^{2} \times \alpha_{1}$

$\tau_{2} = I_{2} \alpha_{2}$

So, $I_{2} = 2 kg \times (0.5 m)^{2} + 2 kg \times (0.5 m)^{2}$

= 1 $kg m^{2}$

as $\tau_{2} = I_{2} \alpha_{2}$

= $1 kg m^{2} \times \alpha_{2}$

Hence, $\tau_{1} = \tau_{2}$

$4 \alpha_{1} = \alpha_{2}$

$\alpha_{1} = \frac{1}{4} \alpha_{2}$

Thus, we can conclude that the new rotation is $\frac{1}{4}$ times that of the first rotation rate.

8 0

3 years ago

Block on inclined plane experience a force due to gravity of 300N straight down. If the slope is inclined at 67.8°to the horizon

Tems11 [23]

Answer:

The component of the force due to gravity perpendicular and parallel to the slope is 113.4 N and 277.8 N respectively.

Explanation:

Force is any cause capable of modifying the state of motion or rest of a body or of producing a deformation in it. Any force can be decomposed into two vectors, so that the sum of both vectors matches the vector before decomposing. The decomposition of a force into its components can be done in any direction.

Taking into account the simple trigonometric relations, such as sine, cosine and tangent, the value of their components and the value of the angle of application, then the parallel and perpendicular components will be:

Fparallel = F*sinα =300 N*sin 67.8° =300 N*0.926⇒ Fparallel =277.8 N
Fperpendicular = F*cosα = 300 N*cos 67.8° = 300 N*0.378 ⇒ Fperpendicular= 113.4 N

<u><em>The component of the force due to gravity perpendicular and parallel to the slope is 113.4 N and 277.8 N respectively.</em></u>

6 0

3 years ago

A soldier throws a grenade horizontally from the top of a cliff. Which of the following curves best describes the path taken by

Natasha_Volkova [10]

Answer:

4. Parabola

Explanation:

The motion of the flight of the grenade is a projectile motion, it's shape is best illustrated using a parabolic diagram.

It's not a circle as the path is not totally round.

It's not an ellipse as the path of motion is not a a completely bounded shape.

Its not a hyperbola as a hyperbola is an open curve with two branches.

Its a parabolic shape because a parabola has just one branch

7 0

3 years ago

A swimmer moves through the water at 2.5 meters per second and experiences a drag force of 240 N. How much power is she generati

mote1985 [20]

-- There's a force of 240N pushing her backwards.

-- She's maintaining a steady speed (of 2.5 m/s) .

-- In order to maintain a steady speed (no acceleration),
the forces on her must be balanced. So she's maintaining
a steady force of 240N forward.

-- Every time she moves 1 m forward, she does work of
(force) x (distance) = 240 joules.

-- She moves 2.5 meters forward every second.
So she's doing (240 x 2.5) = 600 joules of work every second.

-- 600 joules per second = 600 watts .

6 0

3 years ago