Select The Correct Answer.Julie Is Cycling At A Speed Of 3.4 Meters/second. If The Combined Mass Of The Bicycle And Julie Is 30 Kilograms, What Is The Kinetic Energy?A. $1.7 \times 10^2$ Joules B. $1.5 \times 10^2$ Joules C.

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Introduction

Kinetic energy is a fundamental concept in physics that describes the energy of motion. It is a measure of the energy an object possesses due to its motion. In this article, we will delve into the concept of kinetic energy, its formula, and how to calculate it using a real-world example.

What is Kinetic Energy?

Kinetic energy is the energy an object possesses due to its motion. It is a measure of the energy an object has due to its velocity. The more an object moves, the more kinetic energy it possesses. Kinetic energy is a scalar quantity, meaning it has only magnitude and no direction.

Formula for Kinetic Energy

The formula for kinetic energy is:

K = (1/2)mv^2

Where:

  • K is the kinetic energy
  • m is the mass of the object
  • v is the velocity of the object

Real-World Example: Julie's Cycling

Let's consider the example given in the problem statement. Julie is cycling at a speed of 3.4 meters/second. If the combined mass of the bicycle and Julie is 30 kilograms, what is the kinetic energy?

Step 1: Convert the mass from kilograms to grams

Since the formula for kinetic energy requires the mass in kilograms, we can convert the mass from kilograms to grams. However, in this case, the mass is already given in kilograms, so we can proceed with the calculation.

Step 2: Calculate the kinetic energy

Using the formula for kinetic energy, we can calculate the kinetic energy as follows:

K = (1/2)mv^2 K = (1/2)(30 kg)(3.4 m/s)^2 K = (1/2)(30 kg)(11.56 m2/s2) K = 168.3 J

Step 3: Convert the kinetic energy to the correct answer format

The kinetic energy is calculated to be 168.3 joules. However, the answer choices are given in the format of $1.7 \times 10^2$ joules. To convert the kinetic energy to this format, we can multiply it by 10^2:

168.3 J x 10^2 = 1.683 x 10^4 J

However, this is not the correct answer. We need to convert the kinetic energy to the format $1.7 \times 10^2$ joules. To do this, we can round the kinetic energy to two significant figures:

K ≈ 1.7 x 10^2 J

Conclusion

In conclusion, the kinetic energy of Julie's bicycle is approximately $1.7 \times 10^2$ joules. This is the correct answer to the problem statement.

Discussion

The concept of kinetic energy is a fundamental aspect of physics. It is a measure of the energy an object possesses due to its motion. In this article, we have discussed the formula for kinetic energy and how to calculate it using a real-world example. We have also seen how to convert the kinetic energy to the correct answer format.

Frequently Asked Questions

  • What is kinetic energy?
  • How is kinetic energy calculated?
  • What is the formula for kinetic energy?
  • How do I convert the kinetic energy to the correct answer format?

Answers

  • Kinetic energy is the energy an object possesses due to its motion.
  • Kinetic energy is calculated using the formula K = (1/2)mv^2.
  • The formula for kinetic energy is K = (1/2)mv^2.
  • To convert the kinetic energy to the correct answer format, you can round the kinetic energy to two significant figures and multiply it by 10^2.

References

  • Halliday, D., Resnick, R., & Walker, J. (2013). Fundamentals of physics. John Wiley & Sons.
  • Serway, R. A., & Jewett, J. W. (2018). Physics for scientists and engineers. Cengage Learning.
    Kinetic Energy Q&A: Frequently Asked Questions =====================================================

Introduction

Kinetic energy is a fundamental concept in physics that describes the energy of motion. In our previous article, we discussed the formula for kinetic energy and how to calculate it using a real-world example. In this article, we will answer some frequently asked questions about kinetic energy.

Q: What is kinetic energy?

A: Kinetic energy is the energy an object possesses due to its motion. It is a measure of the energy an object has due to its velocity.

Q: How is kinetic energy calculated?

A: Kinetic energy is calculated using the formula K = (1/2)mv^2, where K is the kinetic energy, m is the mass of the object, and v is the velocity of the object.

Q: What is the formula for kinetic energy?

A: The formula for kinetic energy is K = (1/2)mv^2.

Q: How do I convert the kinetic energy to the correct answer format?

A: To convert the kinetic energy to the correct answer format, you can round the kinetic energy to two significant figures and multiply it by 10^2.

Q: What is the unit of kinetic energy?

A: The unit of kinetic energy is joules (J).

Q: Can kinetic energy be negative?

A: No, kinetic energy cannot be negative. Kinetic energy is always a positive quantity.

Q: Is kinetic energy a scalar or vector quantity?

A: Kinetic energy is a scalar quantity, meaning it has only magnitude and no direction.

Q: Can kinetic energy be transferred from one object to another?

A: Yes, kinetic energy can be transferred from one object to another through collisions or other interactions.

Q: Is kinetic energy a conserved quantity?

A: Yes, kinetic energy is a conserved quantity, meaning it cannot be created or destroyed, only transferred from one object to another.

Q: Can kinetic energy be converted to other forms of energy?

A: Yes, kinetic energy can be converted to other forms of energy, such as potential energy, thermal energy, or sound energy.

Q: Is kinetic energy related to the motion of an object?

A: Yes, kinetic energy is directly related to the motion of an object. The faster an object moves, the more kinetic energy it possesses.

Q: Can kinetic energy be measured directly?

A: No, kinetic energy cannot be measured directly. It must be calculated using the formula K = (1/2)mv^2.

Conclusion

In conclusion, kinetic energy is a fundamental concept in physics that describes the energy of motion. We have answered some frequently asked questions about kinetic energy, including its formula, unit, and relationship to motion. We hope this article has been helpful in understanding kinetic energy.

Frequently Asked Questions (FAQs)

  • What is kinetic energy?
  • How is kinetic energy calculated?
  • What is the formula for kinetic energy?
  • How do I convert the kinetic energy to the correct answer format?
  • What is the unit of kinetic energy?
  • Can kinetic energy be negative?
  • Is kinetic energy a scalar or vector quantity?
  • Can kinetic energy be transferred from one object to another?
  • Is kinetic energy a conserved quantity?
  • Can kinetic energy be converted to other forms of energy?
  • Is kinetic energy related to the motion of an object?
  • Can kinetic energy be measured directly?

Answers

  • Kinetic energy is the energy an object possesses due to its motion.
  • Kinetic energy is calculated using the formula K = (1/2)mv^2.
  • The formula for kinetic energy is K = (1/2)mv^2.
  • To convert the kinetic energy to the correct answer format, you can round the kinetic energy to two significant figures and multiply it by 10^2.
  • The unit of kinetic energy is joules (J).
  • No, kinetic energy cannot be negative.
  • Kinetic energy is a scalar quantity, meaning it has only magnitude and no direction.
  • Yes, kinetic energy can be transferred from one object to another.
  • Yes, kinetic energy is a conserved quantity.
  • Yes, kinetic energy can be converted to other forms of energy.
  • Yes, kinetic energy is directly related to the motion of an object.
  • No, kinetic energy cannot be measured directly.

References

  • Halliday, D., Resnick, R., & Walker, J. (2013). Fundamentals of physics. John Wiley & Sons.
  • Serway, R. A., & Jewett, J. W. (2018). Physics for scientists and engineers. Cengage Learning.