It is generally a good idea to gain an understanding of the "size" of units. Consider the objects and calculate the kinetic energy of each one. A ladybug weighing 37.3 mg flies by your head at 3.79 km/h. J A 7.15 kg bowling ball slides (not rolls) down an alley at 21.1 km/h. J A car weighing 1060 kg moves at a speed of 47.5 km/h.
Kinematics
A machine is a device that accepts energy in some available form and utilizes it to do a type of work. Energy, work, or power has to be transferred from one mechanical part to another to run a machine. While the transfer of energy between two machine parts, those two parts experience a relative motion with each other. Studying such relative motions is termed kinematics.
Kinetic Energy and Work-Energy Theorem
In physics, work is the product of the net force in direction of the displacement and the magnitude of this displacement or it can also be defined as the energy transfer of an object when it is moved for a distance due to the forces acting on it in the direction of displacement and perpendicular to the displacement which is called the normal force. Energy is the capacity of any object doing work. The SI unit of work is joule and energy is Joule. This principle follows the second law of Newton's law of motion where the net force causes the acceleration of an object. The force of gravity which is downward force and the normal force acting on an object which is perpendicular to the object are equal in magnitude but opposite to the direction, so while determining the net force, these two components cancel out. The net force is the horizontal component of the force and in our explanation, we consider everything as frictionless surface since friction should also be calculated while called the work-energy component of the object. The two most basics of energy classification are potential energy and kinetic energy. There are various kinds of kinetic energy like chemical, mechanical, thermal, nuclear, electrical, radiant energy, and so on. The work is done when there is a change in energy and it mainly depends on the application of force and movement of the object. Let us say how much work is needed to lift a 5kg ball 5m high. Work is mathematically represented as Force ×Displacement. So it will be 5kg times the gravitational constant on earth and the distance moved by the object. Wnet=Fnet times Displacement.
![**Understanding Units and Kinetic Energy Calculations**
It's important to understand the relative size of units when comparing different objects. Below are examples where you can calculate the kinetic energy of each object:
1. **Ladybug**
- Weight: 37.3 mg
- Speed: 3.79 km/h
- \( \text{Kinetic Energy (in J)} \): [Calculate here]
2. **Bowling Ball**
- Weight: 7.15 kg
- Speed: 21.1 km/h
- \( \text{Kinetic Energy (in J)} \): [Calculate here]
3. **Car**
- Weight: 1060 kg
- Speed: 47.5 km/h
- \( \text{Kinetic Energy (in J)} \): [Calculate here]
**Formula for Kinetic Energy**:
\[ KE = \frac{1}{2} mv^2 \]
- \( m \) = mass (kg)
- \( v \) = speed (m/s)
Convert speeds from km/h to m/s by using the conversion factor \( \frac{1 \text{ km/h}}{3.6 \text{ m/s}} \).
**Additional Information**:
- Proper unit conversion is crucial.
- Ensure all figures are in the correct units before calculations.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fb4fcfcba-e514-40cd-a23f-a99b46943f83%2F6f31f809-027a-4d94-9f30-0109af992c7d%2Famzyhdh.png&w=3840&q=75)
![**Kinetic Energy Problem**
*A car weighing 1060 kg moves at a speed of 47.5 km/h.*
The box provided is for calculating the kinetic energy of the car and expressing it in joules (J).
**Multiple Choice Question:**
*Based on the kinetic energy of each object, which of the scenarios likely describes an object possessing 1 J of kinetic energy?*
- ○ a tiger running after prey
- ● an elephant running across a field (selected option)
- ○ a beetle walking across a jungle floor
- ○ a mosquito flying through a swamp
- ○ a cat walking down a sidewalk
**Additional Information:**
This problem helps explore the concept of kinetic energy, which can be calculated using the formula:
\[ KE = \frac{1}{2}mv^2 \]
where \( m \) is mass in kilograms and \( v \) is velocity in meters per second.
**Answer Explanation:**
The selected option "an elephant running across a field" is highlighted as the scenario that is most likely to possess 1 J of kinetic energy based on assumptions about typical speeds and masses of the objects listed.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fb4fcfcba-e514-40cd-a23f-a99b46943f83%2F6f31f809-027a-4d94-9f30-0109af992c7d%2Ft51zrlq.png&w=3840&q=75)
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