A box 5cm long, 4cm wide and 6cm high would have what volume? Show your work

podryga [215]

Your answer is "surface of a sphere"

Hope this helps.

3 0

2 years ago

Which scientific law describes the relationship between action and reaction force pairs? Newton's third law of motion Kepler's l

Hitman42 [59]

Newton's third law of motion

Explanation:

Newton's third law of motion states that:

"When an object A exerts a force on an object B (action force), then object B exerts an equal and opposite force (reaction force) on object A"

It is important to note that this law is always valid, even when it seems it is not.

Consider for example the gravitational force that the Earth exerts on your body (= your weight). We can say that this is the action force. It may seems that there is no reaction force in this case. However, this is not true: in fact, your body also exerts an equal and opposite force on the Earth, and this is the reaction force. The reason that explains why we don't notice any effect on Earth due to this force is that the mass of the Earth is much larger than your mass, therefore the acceleration produced on the Earth because of the force you apply is negligible.

It is also important to note that the action-reaction pair of forces always act on two different objects, so they never appear in the same free-body diagram.

Learn more about Newton's third law of motion:

brainly.com/question/11411375

#LearnwithBrainly

7 0

3 years ago

A girl is sledding down a slope that is inclined at 30º with respect to the horizontal. The wind is aiding the motion by providi

OleMash [197]

Answer:

The sled required 9.96 s to travel down the slope.

Explanation:

Please, see the figure for a description of the problem. In red are the x and y-components of the gravity force (Fg). Since the y-component of Fg (Fgy) is of equal magnitude as Fn but in the opposite direction, both forces get canceled.

Then, the forces that cause the acceleration of the sled are the force of the wind (Fw), the friction force (Ff) and the x-component of the gravity force (Fgx).

The sum of all these forces make the sled move. Finding the resulting force will allow us to find the acceleration of the sled and, with it, we can find the time the sled travel.

The magnitude of the friction force is calculated as follows:

Ff = μ · Fn

where :

μ = coefficient of kinetic friction

Fn = normal force

The normal force has the same magnitude as the y-component of the gravity force:

Fgy = Fg · cos 30º = m · g · cos 30º

Where

m = mass

g = acceleration due to gravity

Then:

Fgy = m · g · cos 30º = 87.7 kg · 9.8 m/s² · cos 30º

Fgy = 744 N

Then, the magnitude of Fn is also 744 N and the friction force will be:

Ff = μ · Fn = 0.151 · 744 N = 112 N

The x-component of Fg, Fgx, is calculated as follows:

Fgx = Fg · sin 30º = m·g · sin 30º = 87.7 kg · 9.8 m/s² · sin 30º = 430 N

The resulting force, Fr, will be the sum of all these forces:

Fw + Fgx - Ff = Fr

(Notice that forces are vectors and the direction of the friction force is opposite to the other forces, then, it has to be of opposite sign).

Fr = 161 N + 430 N - 112 N = 479 N

With this resulting force, we can calculate the acceleration of the sled:

F = m·a

where:

F = force

m = mass of the object

a = acceleration

Then:

F/m = a

a = 479N/87.7 kg = 5.46 m/s²

The equation for the position of an accelerated object moving in a straight line is as follows:

x = x0 + v0 · t + 1/2 · a · t²

where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

Since the sled starts from rest and the origin of the reference system is located where the sled starts sliding, x0 and v0 = 0.

x = 1/2· a ·t²

Let´s find the time at which the position of the sled is 271 m:

271 m = 1/2 · 5.46 m/s² · t²

2 · 271 m / 5.46 m/s² = t²

t = 9.96 s

The sled required almost 10 s to travel down the slope.

8 0

3 years ago

Identify the pros and cons of using mirrors versus lenses in each of the following applications:

disa [49]

Answer:

Explanation:

A lens – An object, usually made of glass, that focuses or defocuses the light that passes through it.

A mirror – A smooth surface, usually made of glass with reflective material painted on the underside, that reflects light so as to give an image of what is in front of it.

Telescope – monocular optical instrument possessing magnification for observing distant objects, especially in astronomy.

Refracting telescopes – are telescopes that use lenses are and those that use concave parabolic mirrors are called reflecting telescopes.

Pros of mirror telescope

• They are easier to construct and not expensive to produce

• made larger and more durable (more light can be directed to the eyepiece which is good)

• cannot have any occlusions

• mirrors have less spherical aberration

• reflect all wavelengths of light equally

• more magnification power for cheaper version

Cons of mirror prisms

• it must also be realigned after cleaning, which can be expensive - maintenance disadvantage

• Reflective Surface Disadvantage

Pros of Lenses telescope

• Easy to use

• More reliable

Cons of Lens telescope

• are not easy to construct and expensive to produce

• May have occlusions

• spherical aberration are more

• Doesnt reflect wavelengths of light equally they bend light differently

• Less magnification power for cheaper version

• heavy

• Longer body

Pro of Mirror periscope

• it helps us to see further than our view that is what is above us or sometimes even below us.

•Light weight

disadvantage:

• it may not work properly and show distorted images due to fog. ; Some have a narrow field of view ; May be detected by others Ungainly (long, takes up space),

•Not as rugged as prisms.

• Maintenance of reflection surface

Pros of Prism periscopes

• incorporated lenses for magnification and function as telescopes.

• They typically employ prisms and total internal reflection instead of mirrors, because prisms, which do not require coatings on the reflecting surface, are much more rugged than mirrors.

• May be fitted with additional optical capabilities such as range-finding and targeting.

Cons.

•mechanically disadvantage: Complex optically ; Some have a narrow field of view ; May be detected by others

Ungainly (long, takes up space)

• Heavy weight

Lens - Terrestrial telescope

Pro: An advantage is that it makes it possible to vary the magnification of the telescope.

Cons- This system has the disadvantage increasing the length of the telescope.

Mirror- Terrestrial telescope (Cassegrain)

Pro: Good for distant terrestrial viewing.

greater magnification is attained.

They are more shorter

Cons- It is not what people expect a telescope to look like.

Slight light loss due to secondary mirror obstruction compared to refractors. Generally not suited for most terrestrial applications nor for to view objects in the sky.

6 0

2 years ago

A 22-turn circular coil of radius 3.00 cm and resistance 1.00 Ω is placed in a magnetic field directed perpendicular to the plan

zloy xaker [14]

Answer:

23.5 mV

Explanation:

number of turn coil 'N' =22

radius 'r' =3.00 cm=> 0.03m

resistance = 1.00 Ω

B= 0.0100t + 0.0400t²

Time 't'= 4.60s

Note that Area'A' = πr²

The magnitude of induced EMF is given by,

lƩl =ΔφB/Δt = N (dB/dt)A

=N[d/dt (0.0100t + 0.0400 t²)A

=22(0.0100 + 0.0800(4.60))[π(0.03)²]

=0.0235

=23.5 mV

Thus, the induced emf in the coil at t = 4.60 s is 23.5 mV

8 0

3 years ago