Answer:
3. If you buy a new cell phone, your opportunity cost is the time you could spend talking on the phone.
Answer:
D. A diet based on what they could find
Explanation:
They only ate what they could find they hunted and they gathered different fruits and stuff they could find
FIRST OF ALL ITS A PHYSICS QUESTION. FIND WORK USING THE FORMULA OF P.E
P.E=<span>Gravitational potential energy is the energy
stored in an object as the result of its vertical position or height.
The energy is stored as the result of the gravitational attraction of
the Earth for the object.
=MGH
=38/10*12*98/10=</span>
<span>446.88JOULES</span>
Answer:
As mentioned in the previous part of this lesson, momentum is a commonly used term in sports. When a sports announcer says that a team has the momentum they mean that the team is really on the move and is going to be hard to stop. The term momentum is a physics concept. Any object with momentum is going to be hard to stop. To stop such an object, it is necessary to apply a force against its motion for a given period of time. The more momentum that an object has, the harder that it is to stop. Thus, it would require a greater amount of force or a longer amount of time or both to bring such an object to a halt. As the force acts upon the object for a given amount of time, the object's velocity is changed; and hence, the object's momentum is changed.
The concepts in the above paragraph should not seem like abstract information to you. You have observed this a number of times if you have watched the sport of football. In football, the defensive players apply a force for a given amount of time to stop the momentum of the offensive player who has the ball. You have also experienced this a multitude of times while driving. As you bring your car to a halt when approaching a stop sign or stoplight, the brakes serve to apply a force to the car for a given amount of time to change the car's momentum. An object with momentum can be stopped if a force is applied against it for a given amount of time.
A force acting for a given amount of time will change an object's momentum. Put another way, an unbalanced force always accelerates an object - either speeding it up or slowing it down. If the force acts opposite the object's motion, it slows the object down. If a force acts in the same direction as the object's motion, then the force speeds the object up. Either way, a force will change the velocity of an object. And if the velocity of the object is changed, then the momentum of the object is changed.
Explanation:
