All categories

3 years ago

The specific heat of iron is 0.45j/gk. The amount of heat needed to raise the temperature of the 12 g of iron by exactly 15k?

Physics

1 answer:

labwork [276]3 years ago

8 0

Answer:

81 J.

Explanation:

From the question given above, the following data were obtained:

Specific heat capacity (C) = 0.45 J/gK.

Temperature change (ΔT) = 15 K

Mass = 12 g

Heat required (Q) =?

The heat required to raise the temperature of iron can be obtained as illustrated below:

Q = MCΔT

Q = 12 × 0.45 × 15

Q = 81 J

Therefore, the heat required to raise the temperature of the iron is 81 J.

You might be interested in

A 4.2-m-diameter merry-go-round is rotating freely with an angular velocity of 0.80 rad????s. Its total moment of inertia is 136

Lina20 [59]

Answer:

A) 0.44 rad/s

B) 3.091 rad/s

Explanation:

Initial angular momentum must be equal to final angular momentum.

W1 = 0.80 rad/s

I = 1360 kgm^2

Initial moment Iw = 0.8 x 1360 = 1088 rad-kg-m^2/s

For second case

I = (65 x 4)4.2 + 1360 = 2452 kg-m2-rad/s

New momentum = 2452 x W2

Where w2 = final angular momentum

= 2452W2

Equating both moment,

1088 = 2452W2

W2 = 0.44 rad/s0

If they were on it before,

Initial momentum

I = 1360 - (60 x 4)4.2

= 352 rad-kg-m^2/s

352W1 = 1088

W1 = 3.091 rad/s

5 0

3 years ago

After it was discovered, astronomers predicted Uranus's orbit using Newton's laws of motion and gravity, which had worked extrem

kotykmax [81]

Answer:

A. Check for other previously undiscovered factors that might alter Uranus's orbit while still allowing it to obey Newton's laws of motion and gravity.

Explanation:

Uranus behaved in a way that Newton's laws of motion could not explain. But this law predicted very well the behavior of other planets, so it could not be totally wrong or discarded, so it was decided to look for whether there was a planet beyond Uranus, which would alter its movement. The search was done and this is how Neptune was discovered, and by adding the attraction that Neptune would have on Uranus, its orbit could be calculated correctly by Newton's laws of motion.

Since Newton's law of gravitation had worked so well it was more likely that there were unknown factors that would alter his movement, rather than the laws no longer working or the data being wrong.

Later Newton's law of gravitation was modified by Einstein to take into account the effects of relativity. But Newton's laws work very well to describe the solar system.

4 0

2 years ago

Describe the action and reaction forces in propulsion devices.

aksik [14]

Answer:

Hello!

I could help you on this ^^

Explanation:

Newton’s Third Law of Motion states, “When one object exerts a force on a second object, the second one exerts a force on the first that is equal in magnitude and opposite in direction.”

-This law is sometimes called the “Law of Action and Reaction”.

-Even though the forces are equal in magnitude (strength) and opposite in direction, they do not cancel each other.

This law addresses two objects, each with only one force exerted on it.

-Each object is exerting one force on the other object.

-Each object is experiencing only one force.

The action and reaction forces are reciprocal (opposite) on an object.

Examples may include:

A swimmer swimming forward:

The swimmer pushes against the water (action force), the water pushes back on the swimmer (reaction force) and pushes her forward.

A ball is thrown against a wall:

The ball puts a force on the wall (action force), and the wall puts a force on the ball (reaction force) so the ball bounces off.

A person is diving off a raft:

The person puts a force on the raft (action force) pushing it, and the raft puts a force on the diver (reaction force) pushing them in the opposite direction.

A person pushes against a wall (action force), and the wall exerts an equal and opposite force against the person (reaction force).

(Not my words)

"The Space Shuttle engines push out hot gases (action force), and the hot gases put a force on the shuttle engines (reaction force) so the shuttle lifts (there is no sling shot doing it)"

6 0

3 years ago

A crane can lift a 900 kg mass to height of 50 m in 2 minutes. Calculate the work

Vera_Pavlovna [14]

Answer:

The work done by the crane is, W = 441000 J

The power of the crane is, p = 3675 watts

Explanation:

Given data,

The mass of the object, m = 900 kg

The object is lifted to the height, h = 50 m

The time taken to lift the mass, t = 2 min

= 120 s

The work done by the crane on the object is equal to the potential energy of the object at that height. It is given by the formula,

W = P.E = mgh joules

Substituting the values in the above equation

W = 900 kg x 9.8 m/s² x 50 m

= 441000 J

The work done by the crane is, W = 441000 J

The power of the crane,

P = W / t

= 441000 J / 120 s

= 3675 watts

Hence, the power of the crane is, p = 3675 watts

8 0

3 years ago

The top walking speed of a fly is 1 cm/s. How far can a fly crawling on the ceiling travel in 6 seconds?

natima [27]

The answer to this question is C.

8 0

3 years ago