How can speed be defined

A certain quantity of steam has a temperature of 100.0 oC. To convert this steam into ice at 0.0 oC, energy in the form of heat

KonstantinChe [14]

Answer:

2452.79432 m/s

Explanation:

m = Mass of ice

$L_s$ = Latent heat of steam

$s_w$ = Specific heat of water

$L_i$ = Latent heat of ice

v = Velocity of ice

$\Delta T$ = Change in temperature

Amount of heat required for steam

$Q_1=mL_s\\\Rightarrow Q_1=m(2.256\times 10^6)$

Heat released from water at 100 °C

$Q_2=ms_w\Delta T\\\Rightarrow Q_2=m4186\times (100-0)\\\Rightarrow Q_2=m0.4186\times 10^6$

Heat released from water at 0 °C

$Q_3=mL_i\\\Rightarrow Q_3=m(333.5\times 10^3)\\\Rightarrow Q_3=m(0.3335\times 10^6)$

Total heat released is

$Q=Q_1+Q_2+Q_3\\\Rightarrow Q=m(2.256\times 10^6)+m0.4186\times 10^6+m(0.3335\times 10^6)\\\Rightarrow Q=3008100m$

The kinetic energy of the bullet will balance the heat

$K=Q\\\Rightarrow \frac{1}{2}mv^2=3008100m\\\Rightarrow v=\sqrt{2\times 3008100}\\\Rightarrow v=2452.79432\ m/s$

The velocity of the ice would be 2452.79432 m/s

6 0

3 years ago

If a cart goes around a turn at 20 km/h ,what remains constant

Vitek1552 [10]

Answer: 4.speed

Explanation:

In this case, we know that the cart remains at a constant 20km/h.

Now, one could say that "the velocity remains constant, because it always is 20km/h"

But remember that velocity is a vector, so this has a direction, and if the cart is going around a turn, then the direction of motion is changing, which tell us that there is acceleration.

But the module of the velocity, the speed, remains constant at 20km/h.

Then the correct option is 4, speed.

7 0

3 years ago

A team of seven psychologist is study love, but each psychologist is working from a different perspective. In your opinion, what

stepladder [879]

Answer:

- Behavioral Psychologists

- Psychodynamic Psychologist

- Biological Psychologist

- Cognitive Psychologist

- Evolutionary Psychologist

- Socio - Cultural Psychologist

- Humanist Psychologist

Explained in explanation section

Explanation:

There are different classes of psychologists but for the purpose of this question we need just 7 that would fit into the study of love. These 7 will be;

1) A behavioral Psychologist might study behaviors associated with love, such as hugging, caressing or kissing.

2) A psychodynamic psychologist might study how a people's challenges with love are caused by unmindful and unresolved conflicts.

3) A biological psychologist might study which chemicals in the brain such as dopamine make people feel loved. He might also study parts of the what parts of the brain are active when people are in love.

4) A cognitive psychologist might study how people's cognitive processes will change when they are in love.

5) An evolutionary psychologist might study how certain actions or behaviors associated with love provided our forefathers with sufficient knowledge to handle their love problems.

6) A sociocultural psychologist might study how people express love in in various cultures across the world.

7) A humanistic psychologist might study the behavior of those who feel most loved and the impact it has in their lives

8 0

3 years ago

A piece of gym equipment states that the maximum load it can hold is 300 kg. Why do you think it is important not to go over thi

Crazy boy [7]

Answer:

The weight limit of 300kg is the maximum amount the machine can handle so it can be dangerous to exceed the maximum load.

5 0

2 years ago

A girl drops a stone from the top a tower 45m tall. At the same time, a boy standing at the base of the tower, projects another

Advocard [28]

Answer:

(i) The stones meet at 1.8 second

(ii) The point at which the stones meet, is 28.8 m above the base of the building and 16.2 m below the top of the building.

Explanation:

(i)

First we consider the stone dropped by the girl. We have data:

Vi = Initial Velocity of Stone = 0 m/s (Since the stone was initially at rest)

t = Time Period

g = 10 m/s²

s₁ = Distance Covered by Stone

Using 2nd equation of motion, we get:

s₁ = Vi t + (0.5)gt²

s₁ = (0)(t) + (0.5)(10)t²

s₁ = 5t² ----- equation (1)

Now, we consider the stone throne vertically upward by the boy. We have data:

Vi = Initial Velocity of Stone = 25 m/s

t = Time Period

g = - 10 m/s² (negative sign due to upward motion)

s₂ = Distance Covered by Stone

Using 2nd equation of motion, we get:

s₂ = Vi t + (0.5)gt²

s₂ = (25)(t) + (0.5)(-10)t²

s₂ = 25t - 5t² ----- equation (2)

At, the point where both the stones meet, the sum of distances covered by both stones must be equal to the height of building (i.e 45 m).

s₁ + s₂ = 45

using values from equation (1) and equation (2)

5t² + 25t - 5t² = 45

25t = 45

t = 45/25

t = 1.8 sec

(ii)

using this value of of t in equation (2)

s₂ = (25)(1.8) - (5)(1.8)²

s₂ = 28.8 m

using this value of of t in equation (1)

s₁ = (5)(1.8)²

s₁ = 16.2 m

Hence, the point at which the stones meet, is 28.8 m above the base of the building and 16.2 m below the top of the building.

6 0

3 years ago