Answer :
Sure, let's address each question with detailed explanations.
### 1. Calculate the momentum of 400 kg car moving at a speed of 50 m/s.
Momentum ([tex]\( p \)[/tex]) is defined by the equation:
[tex]\[ p = m \cdot v \][/tex]
where [tex]\( m \)[/tex] is the mass and [tex]\( v \)[/tex] is the velocity.
- Mass [tex]\((m)\)[/tex]: 400 kg
- Velocity [tex]\((v)\)[/tex]: 50 m/s
[tex]\[ p = 400\, \text{kg} \times 50\, \text{m/s} \][/tex]
[tex]\[ p = 20000\, \text{kg} \cdot \text{m/s} \][/tex]
So, the momentum of the car is 20000 kg·m/s.
### 2. What are the physics principles demonstrated in Newton's cradle?
Newton's cradle primarily demonstrates two key physics principles:
- Conservation of Momentum: The total momentum of a closed system is conserved before and after collisions.
- Conservation of Energy: The total energy in an isolated system remains constant over time. In Newton's cradle, this is typically seen in the transfer of kinetic energy from one ball to the next.
### 3. Calculate the potential energy of a ball at a height of 3m when the mass of the ball is 0.5 kg.
Potential energy ([tex]\( PE \)[/tex]) due to gravity is calculated by:
[tex]\[ PE = m \cdot g \cdot h \][/tex]
where [tex]\( m \)[/tex] is the mass, [tex]\( g \)[/tex] is the acceleration due to gravity, and [tex]\( h \)[/tex] is the height.
- Mass [tex]\((m)\)[/tex]: 0.5 kg
- Gravity [tex]\((g)\)[/tex]: 9.8 m/s[tex]\(^2\)[/tex]
- Height [tex]\((h)\)[/tex]: 3 m
[tex]\[ PE = 0.5\, \text{kg} \times 9.8\, \text{m/s}^2 \times 3\, \text{m} \][/tex]
[tex]\[ PE = 1.5 \times 9.8 \][/tex]
[tex]\[ PE = 14.7\, \text{Joules} \][/tex]
So, the potential energy of the ball is 14.7 Joules.
### 4. Find the kinetic energy of a 0.030 kg bullet moving at 100 m/s.
Kinetic energy ([tex]\( KE \)[/tex]) is given by:
[tex]\[ KE = \frac{1}{2} m v^2 \][/tex]
where [tex]\( m \)[/tex] is the mass and [tex]\( v \)[/tex] is the velocity.
- Mass [tex]\((m)\)[/tex]: 0.030 kg
- Velocity [tex]\((v)\)[/tex]: 100 m/s
[tex]\[ KE = \frac{1}{2} \times 0.030\, \text{kg} \times (100\, \text{m/s})^2 \][/tex]
[tex]\[ KE = 0.015 \times 10000 \][/tex]
[tex]\[ KE = 150\, \text{Joules} \][/tex]
So, the kinetic energy of the bullet is 150 Joules.
### 5. What is the difference between work and power?
- Work: It is the energy transferred to or from an object through the application of force along a displacement. It is a scalar quantity and is measured in Joules (J).
[tex]\[ \text{Work} = \text{Force} \times \text{Displacement} \][/tex]
- Power: It is the rate at which work is done or energy is transferred over time. It is also a scalar quantity and is measured in Watts (W).
[tex]\[ \text{Power} = \frac{\text{Work}}{\text{Time}} \][/tex]
In essence, while work is a measure of energy, power is a measure of how quickly that energy is used or transferred.
### 6. Calculate the power used to do 100 joules of work in 50 seconds.
Power ([tex]\( P \)[/tex]) is calculated by:
[tex]\[ P = \frac{W}{t} \][/tex]
where [tex]\( W \)[/tex] is the work done and [tex]\( t \)[/tex] is the time taken.
- Work [tex]\((W)\)[/tex]: 100 Joules
- Time [tex]\((t)\)[/tex]: 50 seconds
[tex]\[ P = \frac{100\, \text{Joules}}{50\, \text{seconds}} \][/tex]
[tex]\[ P = 2\, \text{Watts} \][/tex]
So, the power used is 2 Watts.
### 7. Write two ways heat is different from temperature.
1. Heat:
- Heat is the energy transferred between systems or objects with different temperatures (thermal energy in transit).
- It is measured in Joules (J).
2. Temperature:
- Temperature is a measure of the average kinetic energy of particles in a substance.
- It is measured in degrees Celsius (°C), Kelvin (K), or Fahrenheit (°F).
### 8. What are three methods of heat transfer? Give one example for each.
The three methods of heat transfer are:
1. Conduction:
- Description: Heat transfer through direct contact between materials.
- Example: Heat transfer through a metal rod.
2. Convection:
- Description: Heat transfer through fluid (liquid or gas) movement.
- Example: Boiling water (heat transfer from the bottom of the pot to the water).
3. Radiation:
- Description: Heat transfer through electromagnetic waves without involving particles.
- Example: Heat from the sun.
Please let me know if you need further explanations or have any additional questions!
### 1. Calculate the momentum of 400 kg car moving at a speed of 50 m/s.
Momentum ([tex]\( p \)[/tex]) is defined by the equation:
[tex]\[ p = m \cdot v \][/tex]
where [tex]\( m \)[/tex] is the mass and [tex]\( v \)[/tex] is the velocity.
- Mass [tex]\((m)\)[/tex]: 400 kg
- Velocity [tex]\((v)\)[/tex]: 50 m/s
[tex]\[ p = 400\, \text{kg} \times 50\, \text{m/s} \][/tex]
[tex]\[ p = 20000\, \text{kg} \cdot \text{m/s} \][/tex]
So, the momentum of the car is 20000 kg·m/s.
### 2. What are the physics principles demonstrated in Newton's cradle?
Newton's cradle primarily demonstrates two key physics principles:
- Conservation of Momentum: The total momentum of a closed system is conserved before and after collisions.
- Conservation of Energy: The total energy in an isolated system remains constant over time. In Newton's cradle, this is typically seen in the transfer of kinetic energy from one ball to the next.
### 3. Calculate the potential energy of a ball at a height of 3m when the mass of the ball is 0.5 kg.
Potential energy ([tex]\( PE \)[/tex]) due to gravity is calculated by:
[tex]\[ PE = m \cdot g \cdot h \][/tex]
where [tex]\( m \)[/tex] is the mass, [tex]\( g \)[/tex] is the acceleration due to gravity, and [tex]\( h \)[/tex] is the height.
- Mass [tex]\((m)\)[/tex]: 0.5 kg
- Gravity [tex]\((g)\)[/tex]: 9.8 m/s[tex]\(^2\)[/tex]
- Height [tex]\((h)\)[/tex]: 3 m
[tex]\[ PE = 0.5\, \text{kg} \times 9.8\, \text{m/s}^2 \times 3\, \text{m} \][/tex]
[tex]\[ PE = 1.5 \times 9.8 \][/tex]
[tex]\[ PE = 14.7\, \text{Joules} \][/tex]
So, the potential energy of the ball is 14.7 Joules.
### 4. Find the kinetic energy of a 0.030 kg bullet moving at 100 m/s.
Kinetic energy ([tex]\( KE \)[/tex]) is given by:
[tex]\[ KE = \frac{1}{2} m v^2 \][/tex]
where [tex]\( m \)[/tex] is the mass and [tex]\( v \)[/tex] is the velocity.
- Mass [tex]\((m)\)[/tex]: 0.030 kg
- Velocity [tex]\((v)\)[/tex]: 100 m/s
[tex]\[ KE = \frac{1}{2} \times 0.030\, \text{kg} \times (100\, \text{m/s})^2 \][/tex]
[tex]\[ KE = 0.015 \times 10000 \][/tex]
[tex]\[ KE = 150\, \text{Joules} \][/tex]
So, the kinetic energy of the bullet is 150 Joules.
### 5. What is the difference between work and power?
- Work: It is the energy transferred to or from an object through the application of force along a displacement. It is a scalar quantity and is measured in Joules (J).
[tex]\[ \text{Work} = \text{Force} \times \text{Displacement} \][/tex]
- Power: It is the rate at which work is done or energy is transferred over time. It is also a scalar quantity and is measured in Watts (W).
[tex]\[ \text{Power} = \frac{\text{Work}}{\text{Time}} \][/tex]
In essence, while work is a measure of energy, power is a measure of how quickly that energy is used or transferred.
### 6. Calculate the power used to do 100 joules of work in 50 seconds.
Power ([tex]\( P \)[/tex]) is calculated by:
[tex]\[ P = \frac{W}{t} \][/tex]
where [tex]\( W \)[/tex] is the work done and [tex]\( t \)[/tex] is the time taken.
- Work [tex]\((W)\)[/tex]: 100 Joules
- Time [tex]\((t)\)[/tex]: 50 seconds
[tex]\[ P = \frac{100\, \text{Joules}}{50\, \text{seconds}} \][/tex]
[tex]\[ P = 2\, \text{Watts} \][/tex]
So, the power used is 2 Watts.
### 7. Write two ways heat is different from temperature.
1. Heat:
- Heat is the energy transferred between systems or objects with different temperatures (thermal energy in transit).
- It is measured in Joules (J).
2. Temperature:
- Temperature is a measure of the average kinetic energy of particles in a substance.
- It is measured in degrees Celsius (°C), Kelvin (K), or Fahrenheit (°F).
### 8. What are three methods of heat transfer? Give one example for each.
The three methods of heat transfer are:
1. Conduction:
- Description: Heat transfer through direct contact between materials.
- Example: Heat transfer through a metal rod.
2. Convection:
- Description: Heat transfer through fluid (liquid or gas) movement.
- Example: Boiling water (heat transfer from the bottom of the pot to the water).
3. Radiation:
- Description: Heat transfer through electromagnetic waves without involving particles.
- Example: Heat from the sun.
Please let me know if you need further explanations or have any additional questions!
