An 8 m long uniform plank of mass 140 kg rests on the side of a pirate ship with 3 meters extended over the edge. How far can a 60 kg prisoner venture past the odge of the ship on the plank before the plank just begins to tip? Please select the correct answer from the choices shown below: A. 1,5 m B. 1.67 m C. 2 m D. 2.33 m Reset Selection
The energy applied to cause vibration can be in the form of air pressure, a stick,a bow, or electricity. A. False B. True
What do.scientists know about the future of the universe? what dark matter is made of why the expansion of the universe is accelerating that stars will eventually burn out causing the universe to become cold and dark that galaxies spin much slower than they should based on visible matter
10. Which of these illustrates how air resistance can change an object's falling speed? A. An astronaut floating in space B. A coin dropped from a building C. A parachute slowing a skydiver D. A boulder rolling off a cliff
What is the center of an atom called? electron cloud proton center photon center nucleus
The first energy shell contains a maximum of __ electrons. Select one: a. 1 b. 2 C. 4 d. 8
4x The statement can be made that atoms and molecules are always in motion. Formulate a reason that solids can exist. A The internal energy of the atoms is not enough to allow the atoms to disassociate from its neighbors. B External energy output is strong enough to allow the atoms to withdraw from its nearest neighbors. C Intermolecular forces are inadequate to allow the atoms to break away from its nearest neighbors. D Activation energy is equivalent to allow the atoms to migrate away from its nearest neighbors.
What does a negative velocity indicate? The object is moving backwards The object is speeding up The object is at rest The object is slowing down
What is the speed of sound in air that students need to remember? 550 meters per second 330 meters per second 250 meters per second 1000 meters per second
How does the speed of sound waves change in different mediums? It only changes in water It only changes in air It remains constant It varies depending on the medium
What is the relationship between velocity and acceleration? Acceleration is the change in velocity over time. Velocity is the change in acceleration over time. Velocity and acceleration are equal and opposite. Velocity and acceleration have nothing to do with each other.
19. The process by which atomic nuclei spontaneously decay is called relative dating radioactivity erosion deposition 20. The time it takes for 50 percent of the nuclei in a radioactive sample to decay to its stable isotope is called the daughter product geologic time the half-life the half-time 21. The scientist who developed the theory of evolution was Harry Hess James Hutton Charles Darwin William Smith
Radloactive nuclel undergo decay because they are unstable. a TRUE b FALSE
Which of the following would cause a change in the speed of a sound wave? a the wave being made by a larger vibration b the wave moving through water C the wave changing medium from a gas to a liquid d the wave being made by a smaller vibration e none of the above
A man pulls a vacuum forward 13.6 m with a force of 33.9 N at a $55.0^{\circ }$ angle. How much work is being done to the vacuum by the man? $W=[?]J$
Select the cause of evaporation. Waves from the ocean Energy in the clouds Heat from the Sun Rain on the ground
True/False: The mass of the object affects the rate at which it falls. True False
If more force pushes two surfaces together, then the friction between the surfaces will __ stay the same increase decrease
Which of the following is the ideal way to apply pressure onto pedals? Gently at first and then with full force Stomping with force, so it reacts With your entire body weight behind it By pressing gradually
Select all of the types of electromagnetic waves that are ionizing radiation. gamma infrared microwave ultraviolet X-ray
