Practice: A radioactive particle weighing 7.20 x 103 ng is found 110 m above the earth’s surface. What is its potential energy?
| Sections | |||
|---|---|---|---|
| Nature of Energy | 6 mins | 0 completed | Learn |
| Kinetic & Potential Energy | 8 mins | 0 completed | Learn |
| First Law of Thermodynamics | 7 mins | 0 completed | Learn |
| Internal Energy | 8 mins | 0 completed | Learn |
| Endothermic & Exothermic Reactions | 7 mins | 0 completed | Learn Summary |
| Heat Capacity | 16 mins | 0 completed | Learn |
| Constant-Pressure Calorimetry | 20 mins | 0 completed | Learn |
| Constant-Volume Calorimetry | 8 mins | 0 completed | Learn |
| Thermal Equilibrium | 9 mins | 0 completed | Learn |
| Thermochemical Equations | 12 mins | 0 completed | Learn Summary |
| Formation Equations | 9 mins | 0 completed | Learn |
| Enthalpy of Formation | 12 mins | 0 completed | Learn Summary |
| Hess's Law | 23 mins | 0 completed | Learn |
| Additional Guides |
|---|
| Enthalpy |
Mechanical Energy is the energy associated with an object's velocity (Kinetic Energy) and its position (Potential Energy).
Kinetic Energy & Potential Energy
The kinetic energy of a gas molecule is connected to its mass in kilograms and velocity in meters per second.
The potential energy of a gas molecule is connected to its mass, acceleration due to gravity and height above the ground.
Example #1: Calculate the kinetic energy (in kJ) of an electron (m = 9.11 x 10-31 kg) moving at 1.59 x 1020 m/s.
Example #2: A neutron weighing 1.67 x 10-27 kg is shot from a laser projector that is mounted 120.0 meters above the ground. What is its speed when it hits the ground?
Progress
0 of 5 completed
Additional Problems
Which of the following is an example of kinetic energy?
A. A ball lodged in a tree
B. A stretched rubber band
C. Water stored in a dam
D. Thermal energy of atoms and molecules
A 10 kg weight is placed on the edge of the roof of a 4-story building. The weight falls to the ground. Where does the weight have the highest potential energy?
A. On the ground
B. During the fall down
C. On the roof
The random motion of gas particles is representative of ______ energy.
A. Kinetic
B. Potential
C. Thermal
D. Light
Suppose you toss a tennis ball upward. (a) Does the kinetic energy of the ball increase or decrease as it moves higher? Explain your answers.
Suppose you toss a tennis ball upward. (b) What happens to the potential energy of the ball as it moves higher? Explain your answers.
Suppose you toss a tennis ball upward. (c) If the same amount of energy were imparted to a ball the same size as a tennis ball but of twice the mass, how high would the ball go in comparison to the tennis ball? Explain your answers.
(a) Calculate the kinetic energy in joules of a 45-g golf ball moving at 61 m/s.
Calculate the kinetic energy in joules of a 45-g golf ball moving at 61 m/s. (b) Convert this energy to calories.
Calculate the kinetic energy in joules of a 45-g golf ball moving at 61 m/s. (c) What happens to this energy when the ball lands in a sand trap?
(a) What is the kinetic energy in joules of an 850-lb motorcycle moving at 66 mph?
What is the kinetic energy in joules of an 850-lb motorcycle moving at 66 mph? (b) By what factor will the kinetic energy change if the speed of the motorcycle is decreased to 33 mph?
What is the kinetic energy in joules of an 850-lb motorcycle moving at 66 mph? (c) Where does the kinetic energy of the motorcycle go when the rider brakes to a stop?
Suppose an Olympic diver who weighs 52.0 kg executes a straight dive from a 10-m platform.At the apex of the dive, the diver is 10.8 m above the surface of the water. (a) What is the potential energy of the diver at the apex of the dive, relative to the surface of the water?
Suppose an Olympic diver who weighs 52.0 kg executes a straight dive from a 10-m platform. At the apex of the dive, the diver is 10.8 m above the surface of the water. (b) Assuming that all the potential energy of the diver is converted into kinetic energy at the surface of the water, at what speed in m/s will the diver enter the water?
Which of the following statements is or are incorrect?1. Homogeneous mixtures are often call solutions.2. A chemical property of water is that it boils at 100 degrees Celsius.3. Kinetic energy is the energy that results from an object’s position or state. a. 1 and 2 onlyb. 2 and 3 onlyc. 1 and 3 onlyd. only one statement (1 or 2 or 3)e. all three statements (1, 2, and 3)