Which body is in equilibrium?
(1) a satellite orbiting Earth in a circular orbit
. No. The forces on it are unbalanced. There's only one force acting on it ... the force of gravity, pulling it toward the center of the Earth. That's a centripetal force, and the satellite is experiencing centripetal acceleration.
(2) a ball falling freely toward the surface of Earth. No. The forces on it are unbalanced. There's only one force acting on it ... the force of gravity, pulling it toward the center of the Earth. The ball is accelerating toward the ground.
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(3) a car moving with a constant speed along a straight, level road. YES.</em> We don't even need to analyze the forces, just look at the car. It's moving in a straight line, and its speed is not changing. The car's acceleration is zero ! That right there tells us that the NET force ... the sum of all forces acting on the car ... is zero. THAT's called 'equilibrium'.
(4) a projectile at the highest point in its trajectory. No. The forces on it are unbalanced. There's only one force acting on it ... the force of gravity, pulling it toward the center of the Earth. The projectile is accelerating toward the ground.
Football helmets that are made with padding are believed to have reduced head injuries especially when a player accidentally collides with an object. This is because the impact of the collision is decreased due to the padding that serves as a shock absorber.
<span>muscles perform Potential->Kinetic->heat potential- energy that can be used and is stored for use kinetic - movement heat- a prime factor of any kinetic relative.
hope it helped</span>
The fact that all phones are slightly different but achieve same primary goal tells us about technology that there can be many different design solutions to address a single problem (option D).
<h3>What is technology?</h3>
Technology is the organization and application of knowledge for practical purposes.
According to this question, many different companies have produced cell phones through technological applications. Although all of the phones are slightly different, they all achieve the same primary goal.
This shows us an intriguing aspect of technology that there can be many different design solutions to address a single problem.
Learn more about technology at: brainly.com/question/9171028
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A. since the universe has no matter or energy on the outside
