Match each media portrayal with the type of behavior the media portrayal is

A sled is moving down a steep hill. The mass of the sled is 50 kg and the net force acting on it is 20 N. What must be done to f

amid [387]

You need to first measure the angle of descent, i.e. the angle the hill makes with the ground. Then identify the forces acting on the sled, split them up into horizontal and vertical components, or into components that are parallel and perpendicular to the hill, and use Newton's second law to determine the components of the sled's acceleration vector.

There are at least 2 forces acting on the sled:

• its weight, pointing downward with magnitude W = m g

• the normal force, pointing perpendicular to the hill and away from the ground with mag. N

The question doesn't specify, but there might also be friction to consider, indicated in the attachment by the vector F pointing parallel to the slope of the hill and opposing the direction of the sled's motion with mag. F.

Splitting up the forces into parallel/perpendicular components is less work. By Newton's second law, the net force (denoted with ∑ or "sigma" here) in a particular direction is equal to the mass of the sled times its acceleration in that direction:

∑ (//) = W (//) = m a (//)

∑ (⟂) = W (⟂) + N = m a (⟂)

where, for instance, W (//) denotes the component of the sled's weight in the direction parallel to the hill, while a (⟂) denotes the component of the sled's acceleration perpendicular to the hill. If there is friction, you need to add -F to the first equation.

If the hill makes an angle of θ with flat ground, then W makes the same angle with the hill so that

W (//) = -m g sin(θ)

W (⟂) = -m g cos(θ)

So we have

-m g sin(θ) = m a (//) → a (//) = -g sin(θ)

-m g cos(θ) + N = m a (⟂) → a (⟂) = 0

where the last equality follows from the fact that the normal force exactly opposes the perpendicular component of the weight. This is because the sled is moving along the slope of the hill, and not into the air or into the ground.

Then the acceleration vector is

a = a (//)

with magnitude

||a|| = a = g sin(θ).

6 0

3 years ago

The ball X has a known position at 3 different times, each 1 second apart. The positions of the ball are (1.8,2.2)m, (4.4,4.8)m,

Mandarinka [93]

Answer:

Explanation:

From the position coordinates given , it appears that the ball moves simultaneously along x and y direction.

Displacement along x direction in one second = 4.4 - 1.8 = 2.6 m

So velocity along x direction V_x = $\frac{2.6}{s}$

Similarly velocity along y direction V_y(1) = $\frac{2.6}{s}$

In the next phase velocity changes both in x and y direction.

velocity in x - direction V_x(2) = [tex]\frac{2}{s}[/tex

Velocity in Y- direction V_y(2) = [tex]\frac{3.1}{s}[/tex

Acceleration in x direction = change of velocity in x direction

= ( 2 - 2.6 ) = -.6 m s⁻²

Acceleration in y direction = ( 3.1 - 2.6 ) = 0.5 m s⁻²

Total acceleration =\sqrt{( -.6 )² + ( .5 )²}

= .78 ms⁻²

6 0

3 years ago

The amount of work done to bring an electron (q = −e) from right side of hydrogen nucleus to left side in the k shell is________

maksim [4K]

Answer:

d) 2Fr

Explanation:

We know that the work done in moving the charge from the right side to the left side in the k shell is W = ∫Fdr from r = +r to -r. F = force of attraction between nucleus and electron on k shell. F = qq'/4πε₀r² where q =charge on electron in k shell -e and q' = charge on nucleus = +e. So, F = -e × +e/4πε₀r² = -e²/4πε₀r².

We now evaluate the integral from r = +r to -r

W = ∫Fdr

= ∫(-e²/4πε₀r²)dr

= -∫e²dr/4πε₀r²

= -e²/4πε₀∫dr/r²

= -e²/4πε₀ × -[1/r] from r = +r to -r

W = e²/4πε₀[1/-r - 1/+r] = e²/4πε₀[-2/r} = -2e²/4πε₀r.

Since F = -e²/4πε₀r², Fr = = -e²/4πε₀r² × r = = -e²/4πε₀r and 2Fr = -2e²/4πε₀r.

So W = -2e²/4πε₀r = 2Fr.

So, the amount of work done to bring an electron (q = −e) from right side of hydrogen nucleus to left side in the k shell is W = 2Fr

6 0

3 years ago

On the ignition switch, the ________ position provides power to electrical equipment including lights, wipers, warning lights an

Katyanochek1 [597]

On the ignition switch, the ACC position provides power to electrical equipment including lights, wipers, warning lights and radio, without turning on the engine.

ACC is an Autonomous cruise control or adaptive cruise control is a system for road vehicles that automatically adjusts the vehicle speed (can increase or decrease the speed) to maintain a safe distance from vehicles ahead.

There are also many other names of Autonomous cruise control such as active cruise control, intelligent cruise control, or radar cruise control.

8 0

3 years ago

Help me please, ;) I could use it

erastova [34]

Answer:

The solution(s) are in order with respect to the attachments

$2.613\:\cdot10^5$ Joules ; 5. Adding the same amount of heat to two different objects will produce the same increase in temperature ; 2. Same speed in both ; 2. A

Explanation:

Diagram 1 ( Liquid Nitrogen ) : So as you can see, we want our units in Joules here, and can therefore multiply the mass of gaseous nitrogen and the latent heat of liquid nitrogen, to cancel the units kg, and receive our solution - in terms of Joules. Let's do it.

q ( energy removed ) = mass of nitrogen $*$ latent heat of liquid nitrogen,

q = 1.3 kg $*$ 2.01 $*$ 10⁵ J / kg = $1.3\:\cdot \:2.01\:\cdot \:\:10^5$ = $10^5\cdot \:2.613$ = $100000\cdot \:2.613$ = $261300$ Joules = $261.3$ kiloJoules = 2.613 $*$ 10⁵Joules is the energy that must be removed

Diagram 2 : The same amount of heat does not necessarily mean the same increase in temperature for two different objects. The increase in temperature depends on the specific heat capacity of the substance. Therefore your solution is 5 ) Adding the same amount of heat to two different objects will produce the same increase in temperature.

Diagram 3 : The temperatures in both glasses are the same, and hence the molecules have the same average speed. Therefore your solution is 2 ) Same speed in both.

Diagram 4 : Glass A has more water molecules, and hence has more thermal energy. Your solution is 2 ) A.

7 0

3 years ago

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