An object is 1.0 cm tall and its inverted image is 4.0 cm tall. what is the exact magnification

A car travels 90 km/h. How long does it take for the car to travel

koban [17]

Answer:

4.44 hr

Explanation:

distance= rate*time

400km/(90 km/hr)=time

time=4.44 hr

4 0

3 years ago

What they did to expand the atomic theory ?

Levart [38]

Answer:Dalton just expanded on the Greek idea of the atom.

Explanation:

7 0

3 years ago

At higher elevations, the boiling point of water decreases, due to the decrease in atmospheric pressure. As a result, what

Effectus [21]

Answer:

The correct answer is option b. At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.

Explanation:

When we boil water at a very high temperature, it turns out that the water boils much faster. This is because the higher we are, there will be less oxygen and less pressure in the atmosphere. This implies that the water vapor becomes steam much faster than as it happens at low temperatures, so less heat will be needed for the water to boil.

That is why if we want to cook an egg, we will have to lower the heat of the kitchen when we put it on the fire, in order to avoid boiling water very quickly. Lowering the heat, then cooking the egg will take much longer.

Given this data, the correct answer is option B, At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.

8 0

4 years ago

When a man stands on a bathroom scale here on Earth, it reads 640 N . Assume each planet to be a perfect sphere with the followi

noname [10]

Answer:

242.19702 N

578.46718 N

681.02785 N

Explanation:

M = Mass of the corresponding planet

r = Radius of the corresponding planet

g = Acceleration due to gravity = 9.81 m/s²

G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²

Mass of person

$m=\frac{W}{g}\\\Rightarrow m=\frac{640}{9.81}=65.23955\ kg$

Mass is the property of an object, it is constant irrespective of the forces acting on it so the mass of the person on each planet would be the same.

Gravitational force on Mars

$F=\frac{GMm}{r^2}\\\Rightarrow F=\frac{6.67\times 10^{-11}\times 6.419\times 10^{23}\times 65.23955}{(3.396\times 10^{6})^2}\\\Rightarrow F=242.19702\ N$

Magnitude of the gravitational force Mars would exert on the man if he stood on its surface is 242.19702 N

Gravitational force on Venus

$F=\frac{GMm}{r^2}\\\Rightarrow F=\frac{6.67\times 10^{-11}\times 4.869\times 10^{24}\times 65.23955}{(6.052\times 10^{6})^2}\\\Rightarrow F=578.46718\ N$

Magnitude of the gravitational force Venus would exert on the man if he stood on its surface is 578.46718 N

Gravitational force on Saturn

$F=\frac{GMm}{r^2}\\\Rightarrow F=\frac{6.67\times 10^{-11}\times 5.685\times 10^{26}\times 65.23955}{(6.027\times 10^{7})^2}\\\Rightarrow F=681.02785\ N$

Magnitude of the gravitational force Saturn would exert on the man if he stood on its surface is 681.02785 N

6 0

4 years ago

g Drop the object again and carefully observe its motion after it hits the ground (it should bounce). (Consider only the first b

Anestetic [448]

Answer:

a) quantity to be measured is the height to which the body rises

b) weighing the body , rule or fixed tape measure

c) Em₁ = m g h

d) deformation of the body or it is transformed into heat during the crash

Explanation:

In this exercise of falling and rebounding a body, we must know the speed of the body when it reaches the ground, which can be calculated using the conservation of energy, since the height where it was released is known.

a) What quantities must you know to calculate the energy after the bounce?

The quantity to be measured is the height to which the body rises, we assume negligible air resistance.

So let's use the conservation of energy

starting point. Soil

Em₀ = K = ½ m v²

final point. Higher

Em_f = U = mg h

Em₀ = Em_f

Em₀ = m g h₀

b) to have the measurements, we begin by weighing the body and calculating its mass, the height was measured with a rule or fixed tape measure and seeing how far the body rises.

c) We use conservation of energy

starting point. Soil

Em₁ = K = ½ m v²

final point. Higher

Em_f = U = mg h

Em₁ = Em_f

Em₁ = m g h

d) to determine if the energy is conserved, the arrival energy and the output energy must be compared.

There are two possibilities.

* that have been equal therefore energy is conserved

* that have been different (most likely) therefore the energy of the rebound is less than the initial energy, it cannot be stored in the possible deformation of the body or it is transformed into heat during the crash

7 0

3 years ago