Calculate the efficiency of a hairdryer that has a total power input of 2000W and a useful power output of 1200W.

Answer:

c.

is the answer please brainliest

Answer:

Exactly 27 m/s

Explanation:

P=mv

P(cannon)=2.7*1.7

P(cannon)=4.59 kg*m/s

P(cannon)=P(tshirt)

4.59=0.17*v

v=27 m/s

Answer:

both

Explanation:

Silicon

Explanation:

The chemical element of atomic number 14, a nonmetal with semiconducting properties, used in making electronic circuits. Pure silicon exists in a shiny dark gray crystalline form and as an amorphous powder

Answer:

The center of mass changes

Explanation:

The higher the center of mass the more likely things are to topple over but the lower it is the more likely to stay put when all 4 wheels are down .

Time = (distance) / (speed)

Time = (450 km) / (100 m/s)

Time = (450,000 m) / (100 m/s)

Time = 4500 seconds (that's 75 minutes)

Note:

This is about HALF the speed of the passenger jet you fly in when you go to visit Grandma for Christmas.

If the International Space Station flew at this speed, it would immediately go ker-PLUNK into the ocean.

The speed of the International Space Station in its orbit is more like 3,100 m/s, not 100 m/s.

Answer: 9.375m/s

Explanation: This is an inelastic collision, so the formula is mv1+mv2=(m1+m2)v-final. My work is a follows:

2500kg(12m/s) + 700kg(0m/s)=(2500kg+700kg)(v-final)

30,000kg(m/s)+0=3200kg(v-final)

30,000kg(m/s)/3200kg=9.375m/s

Answer:

Bell makers still use bronze because it has desirable properties, such as hardness and sound quality. The atomic structure of a pure metal is orderly and allows electrons to flow freely through the material. In bronze, the addition of tin to copper restricts the movement of the copper atoms.

Answer:

[tex]5.12\:\text{m/s}[/tex]

Explanation:

From the conservation of momentum, the total momentum of the system before and after the collision must be the same. Therefore, let the momentum of Homeboy Joe be [tex]p_b[/tex] and let the mass of Homegirl Jill be [tex]p_j[/tex]. We can write the following equation:

[tex]p_{bi}+p_{ji}=p_{bf}+p_{jf}[/tex], where subscripts [tex]i[/tex] and [tex]f[/tex] represent initial and final momentum respectively.

The momentum of an object is given by [tex]p=mv[/tex].

Therefore, we have:

[tex]m_{b}v_{bi}+m_{j}v_{ji}=m_{b}v_{bf}+m_{b}v_{jf}[/tex] (some messy subscripts but refer to the values being plugged in you're confused what corresponds with what).

Plugging in values, we have:

[tex]99.5\cdot 6.65 + 68.8\cdot (-1.10)=99.5\cdot 2.35+ 68.8\cdot v_{jf}[/tex].

Solving, we get:

[tex]v_{jf}=\frac{99.5\cdot 6.65+68.8\cdot (-1.10)-99.5\cdot2.35}{68.8},\\v_{jf}=5.11875,\\v_{jf}\approx \boxed{5.12\:\text{m/s}}[/tex].

It's important to note that velocity is vector quantity, so the negative velocity assigned to Jill simply implies she is moving at [tex]1.10\:\text{m/s}[/tex] in the opposite of Joe's direction. After the collision, she is now moving [tex]5.12\:\text{m/s}[/tex] in the same direction that Joe was initially moving, due to Joe's relatively large mass and initial velocity.

Answer:

I don't know I'm sorry I will tell you another answer asks me to

Answer:i f I understand your question correctly, the formula is as follows:

Note: The sign convention is based on distances which are measured from the lens to the object or image of regard. Distances measured in the same direction the light is moving are positive and distances measured in the opposite direction the light is moving are negative.

The measurements are in meters

The “ambient” index of refraction is assumed to be n=1.00

The inverse of the object distance plus the dioptric power of the lens (convex—positive and concave—negative) equals the inverse of the image distance.

Or 1/Od +Dl =1/Id

Please note, it has been a long time since I thought about teaching this concept to students.

Explanation:

Answer:

2. wavelength

Explanation:

Light moves in waves. Light waves are different from sound waves in that light travels in transverse waves (as opposed to longitudinal, which is how sound waves travel). A light wave that travels in a direction is called a light ray.

Just like other waves, light waves have a wavelength and amplitude. The wavelength determines the color; we will learn more about this in the lesson on color. The amplitude of a light wave determines the brightness. Just as large amplitudes in sound waves result in sounds with greater intensities (louder sounds), large amplitudes in light waves result in light with greater intensity (brighter light).

Answer:

Explanation:

Use kinematics equations

You have Vi=10m/s and Vf=50m/s and t=2s

Use equation Vf=Vo+at      50=10+a(2)

50=10+2a

40=2a

a=20 m/s^2

Answer:

Using the Newton equation

V²=U² +2as

Given; V=9.2m/s U = 0m/s( because it starts from rest)

S=26.2m.

9.2²=0²+2(26.2)a

a =9.2²/2(26.2)

a=84.6/52.4

a=1.60m/s²

Answer:

2.A

3.D

Explanation:

HOPE THIS HELPS!! :)

Answer:

below

Explanation:

According to Newtons Second Law of Motion, also known as the Law of Force and Acceleration, a force upon an object causes it to accelerate according to the formula net force = mass x acceleration. So the acceleration of the object is directly proportional to the force and inversely proportional to the mass.

Answer:

Answer is the last option, d

Explanation:

edge 2021

Answer:

The correct option is (a)

Explanation:

Impulse is given by the product of force and time. It is denoted by J. So,

[tex]J=F\times t[/tex]

or

[tex]F=\dfrac{J}{t}[/tex]

It can be seen that the relation between the force and the impact time is inverse. Hence, the impact force and impact time possess inverse relation.  

Answer:

a mixture

since it had the power to separate as the question says

hope it helps!!!!!!!!!!!!!!!

Answer:

Plane mirror.

Explanation:

A plain mirror is a mirror with a flat reflecting surface and is made of ordinary glass.

Reflection can be defined as a phenomenon which typically involves a change in the direction of a ray of light or waves as it falls on a smooth surface.

Simply stated, reflection occurs when a ray of light or wavefronts bounces off a smooth surface such as a plane mirror.

Generally, the angle of reflection equals the angle of incidence when a light ray strikes or hits a plane mirror.

The properties or characteristics of the images formed by a plane mirror include;

I. They are virtual and erect (upright).

II. It is the same size as the object formed.

III. It has the same distance from the plane mirror as the distance of the object from the mirror.

Answer:

4 x the frequncy

Explanation:

So 4 x the number

Answer: the first option: "the period of revolution of the Moon around Earth"

Answer:

The answer your looking for would be D.

Explanation: The other answers don't make any sense you can cancel them out D is the the answer the period of rotation of the moon around its axis.

Answer:

Explanation:

A cell

Answer:

Hope this will help you.

Answer:

by using formula,

wavelength= velocity/frequency

= 120/6

= 20 meter

Ans: 20 meter

Answer:

wavelength= velocity

= 120/6= 20 meter

Explanation:

Answer:

D in pairs

Explanation:

Forces always come in pairs - equal and opposite action-reaction force pairs.

Answer:

You'll see it without noticing

Explanation:

for example: Magnets can pull to one thing, but using the other side of the magnet with the other magnet can push away the magnets, and turn it to their way of pulling, also electricity, movement, were making energy everyday, just by moving

Answer:

Into sound and heat energy due to friction.