This is the question

Answer:

11:10 will be the time. reflection causes the object to be flipped when you see its image at the mirror

Answer:

(a) 0.42 m/s²

(b) 83 N

Explanation:

Assuming g = 10 m/s².

Draw free body diagrams for the child and the chair.

There are three forces on the child:

Tension force T pulling up,

Weight force Mg pulling down,

and normal force N pushing up.

There are three forces on the chair:

Tension force T pulling up,

Weight force mg pulling down,

and normal force N pushing down.

Sum of forces on the child in the y direction:

∑F = ma

T + N − Mg = Ma

Sum of forces on the chair in the y direction:

∑F = ma

T − N − mg = ma

Add the equations together to find the acceleration.

2T − Mg − mg = Ma + ma

a = (2T − Mg − mg) / (M + m)

a = g (2T − Mg − mg) / (Mg + mg)

a = (10 m/s²) (2 × 250 N − 320 N − 160 N) / (320 N + 160 N)

a = 0.42 m/s²

Plug into either equation to find the normal force.

T + N − Mg = Ma

250 N + N − 320 N = (320 N / 10 m/s²) (0.42 m/s²)

N = 83 N

Answer:

The height of the wave is determined by the wind strength and fetch.

Explanation:

The height of the wave is determined by the wind strength and fetch.

The more the strength and the more the fetch size the more will be the height of the wave.

Remember as the wave approaches the coast its wavelength decreases and the wave height increases, whereas when the wave goes away from the coast its wavelength increases and height decreases.

Answer:

Space in the astronomy and cosmology space is 3 dimensional region and earth atmosphere end is called space.

Explanation:

Space is the everything of the top earth atmosphere moon, starts, milky way, black hole and GPS satellites an distant,space also called between stars,moon,planet.

Space is all the extends far in all directions, space is finite unbound space surface of the earth has finite are no beginning or not end.

Space contains there are three dimensions is called 3 D space,an space is to refer an interval during signal transmitted also used by the character, bytes, words and octets in  digital signal.

space is that term can refer to various in science, communications and mathematics,and maintain orbits for responsible time, space is usually to begin at the lowest attitude satellites  can maintain orbits.

space coordinates are uniquely define the location of any particular point  and that continuum requires more than coordinates,and the number of dimensions and conventional space or digital communications during the  signal represents logic is 0 words in a digital signal.  

Explanation:

because the moon has less mass than earth, the force due to gravity at the lunar surface is only about 1/6 that on earthso,the weight of a body on earth is 6×5N =30N

Answer: React with the skin

Explanation:

lab safety test Safety goggles and an apron must be worn when handling chemicals labeled corrosive because they React with the skin

Answer:

Explanation:

[tex]m =800kg\\v = 15\\\\K.E = \frac{1}{2}mv^2\\ K.E= \frac{1}{2} \times 800\times 15^2\\= 400 \times 225\\= 90000 joules\\= 90 kilojoules[/tex]

Answer:

○ 0 [tex]\checkmark[/tex]

Explanation:

Even if the athelete runs four laps of a 400 m track, its displacement will be 0 because the displacement is the shortest distance from its to final position. And, here the final and initial position is same since he comes to its initial position after covering certain distance. So, displacement is 0.

Answer:

[tex]\Large \boxed{\mathrm{5.67 \ seconds }}[/tex]

Explanation:

[tex]\displaystyle \mathrm{acceleration \ = \ \frac{final \ velocity - initial \ velocity }{elapsed \ time}}[/tex]

[tex]\displaystyle A \ = \ \frac{V_f - V_i }{t}[/tex]

[tex]\displaystyle 3 \ = \ \frac{25 - 8 }{t}[/tex]

[tex]\displaystyle 3 \ = \ \frac{17 }{t}[/tex]

[tex]\displaystyle t \ = \ \frac{17 }{3} \approx 5.67[/tex]

Answer:

it will be 8ms-1

Explanation:

MaUa+MbUb=MaVa+MbVb

Answer:

The answer is (a.) An upward force balances the downward force gravity on the skydiver

The skydiver is falling at a constant velocity because the upward force is balancing the downward force of gravity. According to Newton, the opposite force balance each other. This is stated in Newton's second law of motion.

The statement that best applies Newton’s laws of motion to explain the skydiver’s motion is that An upward force balances the downward force of gravity on the skydiver.

Newton's 3rd law often applies to skydiving.

When gravity is not acting upon the skydivers they would continue moving in the direction the vehicle they jumped from was moving.

If no air resistance takes place, then the skydivers would still accelerating at 9.8 m/s until they hit the ground.

The skydiver after leaving the aircraft will accelerates downwards due to the force of gravity

usually as there is no air resistance acting in the upwards direction, and there is a resultant force acting downwards, the skydiver will accelerates towards the ground.

Learn more from

https://brainly.com/question/12666434

Answer:

Explanation:

We shall represent the point of destination and point of new starting point in vector form .

i and j will represent east and north .

point of destination = 123 j

starting point = 112 i

distance between the two

D = 123 j - 112 i

magnitude of D = √ ( 123² + 112² )

= 166.35 km

Direction of D

Tanθ = -  123 / 112

= - 1.09

θ = 132.54 degree from east in positive angle .

Answer:

1) 1,157*10⁻⁵ day; 2) 604800 sec.; 3) 0.5 m.

Explanation:

1) 1 second into one day:

one day consists of 24 hours, it means 24*3600=86400 seconds. Then 1 second is 1/86400 day or 1,157*10⁻⁵ day.

2) 1 week into seconds:

1 day consists of 3600*24=86400 seconds, then the week is 7*86400=604800 seconds.

3) 50 cm into meter:

100 cm is one meter, then 50 cm is 0.5 meter.

PS. note, there is not the only way to perform conversion.

Answer:

The work done is -176.4 J.

Explanation:

Given that,

Mass = 1.0 kg

An elevation of  2 m to an elevation of 20 m.

Suppose,  Find the work done by the gravitational field of the earth?

We need to calculate the force

Using formula of force

[tex]F=mg[/tex]

Put the value into the formula

[tex]F=1.0\times9.8[/tex]

[tex]F=9.8\ N[/tex]

We need to calculate the displacement

Using formula of displacement

[tex]Displacement = s_{2}-s_{1}[/tex]

[tex]s=20-2=18\ m[/tex]

The direction of displacement is upward.

Since gravitational force is downwards and displacement is upwards,

Then the angle is 180°.

We need to calculate the work done

Using formula of work

[tex]W=f\cdos s\cos\theta[/tex]

[tex]W=9.8\times18\cos180[/tex]

[tex]W=-176.4\ J[/tex]

Hence, The work done is -176.4 J.

Answer:

The correct option is energy levels

Explanation:

Rutherford's model of an atom suggests that an atom has a tiny positively charged central mass (now called the nucleus) which is surrounded by electrons (negatively charged) in a cloud-like manner.

Bohr's model went a bit further than the Rutherford's model in describing an atom by suggesting that the electrons which surrounds in the nucleus travel in fixed circular orbits. This description by Bohr was able to describe the energy levels of orbitals which assumes that smallest orbitals have the lowest energy while the largest orbitals have the highest energy.

Answer:

energy levels

hope this helped!

Explanation:

Mercury in a glass tube.

Answer: 50 Pa

Explanation:

Pressure = Force/Area

Pressure = N/m^2

Pressure = 1250/25

Pressure = 50

Pressure = 50 Pa

please click thanks and mark brainliest if you like :)

Answer:

50 pascal

Explanation:

Force=1250N

Area=25m^2 [ pressure=force/area]

P=F/A

1250/25=50

Answer:

13.4 m/s

Explanation:

Given:

Δx = 20 m

v₀ = 10 m/s

a = 2 m/s²

Find: v

v² = v₀² + 2aΔx

v² = (10 m/s)² + 2 (2 m/s²) (20 m)

v = 13.4 m/s

Answer:

Those reaction in which one element replaces another element form its place is called Single displacement reaction

Answer:

d = 343 m

Explanation:

Given that,

You notice that an echo took 2 seconds before you heard the echo of your yell.

We need to find that how far away is the canyon wall that reflected your yell. It means we need to find the distance.

The distance covered by an object is given by :

d = v × t

v is speed of sound in air, v = 343 m/s

The sound took 1 s to reach the wall and 1 s back to you.

It means that,

d = 343 × 1

d = 343 m

So, canyon will reflect your yell at a distance of 343 m

Answer:

20 m

Explanation:

The ball travels 4 m up, then 16 m down.  It travels a total distance of 20 m.

Answer:

60.00

Explanation:

you welcome

Answer:

A. velocity and time

Explanation:

A force can be define as an agent which has the capacity to change the state of an object. It can either increase the velocity of a body, change its direction of motion or cause a moving object to come to rest.

From Newton's second law of motion;

F = ma

where F is the force on the object, m is the mass of the object and a is the acceleration of the object. The unit of force is kgm/[tex]s^{2}[/tex] or Newtons.

a = [tex]\frac{change in velocity}{change in time}[/tex]

In the given question, apart from the mass of the object which is constant, the students should take the measurements of the velocity and time in each trial so as to calculate the required acceleration.

Answer:

mass and acceleration!

Explanation:

Because i am in class just like you and got it wrong because i didn't choose   my first answer:(

average speed of the car is 23.9 km/h

Answer:

The derivative of a constant term is always 0. So the acceleration of the body would be zero. Hence, the acceleration of a body moving with uniform velocity will always be zero.

Answer:

1000meters

Explanation:

Let the wavelength of the radio wave be W and it's frequency be f. If the wavelength of a radio wave varies inversely as its frequency, then W∝1/f

W = k/f where k is the constant of proportionality.

k = Wf

If a wave with a frequency of 1800 kilohertz has a length of 200 meters, then k = 1800×200

k = 360,000kHzm

To get the length of a wave with a frequency of 360 kilohertz, we will substitute the value of k and f = 360kHz into the initial formula i.e

W = k/f

W = 360,000/360

W = 1000meters

Hence the length of a wave with a frequency of 360 kilohertz is 1000meters

Answer:

0.76 mg/s

Explanation:

0.46 kg/week × (1 week / 7 days) × (1 day / 24 hrs) × (1 hr / 3600 s) × (1000 g/kg) × (1000 mg/g) = 0.76 mg/s

Answer:

The atom is mostly empty space.

Explanation:

Ernest Rutherford in the year 1911 developed a model of an atom. In his model the atom was shown that the atom is mostly empty spaces composed of negative electrons which orbits round a positive nucleus just like planets revolving round the sun.

Rutherford came up with this model by performing experiments in 1909 which involves the scattering of alpha particles on a thin gold foil. From this experiments he came up with his model.

Answer:

A!

Explanation:

The atom is mostly empty space.