Exam 6: Circular Motion,orbits,and Gravity

The figure shows a 3.0 kg ball tied to the end of a 50 cm long string being swung in a circle in a vertical plane at constant speed.The center of the circle is h = 510 cm above the floor.The ball is swung at the minimum speed necessary to make it over the top without the string going slack.If the string is released at the instant the ball is at the top of the loop,how far to the right of the center of the circle does the ball hit the ground?

-In the table,the mass of Ekapluto is closest to:

In an amusement park ride,passengers stand inside an 8 m radius cylinder.Initially,the cylinder rotates with its axis oriented along the vertical.After the cylinder has acquired sufficient speed,it tilts into a vertical plane,that is,the axis tilts into the horizontal,as shown in the figure.Suppose that,once the axis has tilted into the horizontal,the ring rotates once every 4.5 s.If a rider's mass is 40 kg,with how much force does the ring push on her at the top of the ride?

Astronauts in orbiting satellites are weightless because they are so far from Earth that its gravitational pull is too weak to feel.

If the Moon were twice the distance from Earth than it currently is,the amount of time it would take to go around Earth would be roughly (the current orbital period of the Moon is four weeks)

The figure shows two wires that are tied to a 710 g mass that revolves in a horizontal circle at a constant speed of 7.5 m/s.What is the tension in the upper wire?

A merry-go-round is spinning at a fixed rate.As a person is walking toward the edge,

Astronauts in orbit are weightless,but they are not beyond the pull of Earth's gravity.How can this be?

A 90 g bead on a 60 cm long string is swung in a vertical circle about a point 200 cm above the floor.The tension in the string when the bead is at the very bottom of the circle is 2.2 N.A very sharp knife is suddenly inserted,as shown in the figure,to cut the string directly below the point of support.How far to the right of the center of the circle does the ball hit the floor?

What is the magnitude of the force exerted by Earth on the Moon?

A person ties a rock to a string and whirls it around in a vertical circle such that sometimes the rock is going straight upward and sometimes the rock is going straight down.She whirls the rock at the minimum speed (constant in time)such that the string is always taut (no sag).If she were to use a longer string,she would have to whirl the rock at a

If an astronaut were exactly half way between Earth and the Moon,the net gravitational force exerted on the astronaut by these two objects would be

If you swing a ball in a vertical circle using a thin string,at the bottom of the circle the tension in the string must be greater than the ball's weight.

An aerobatic aircraft is to perform a spiral maneuver.If the engine provides a tangential acceleration of 5.41 m/s²,what is the radial acceleration it will experience at the end of a circle 30.8 m in radius,if the speed at the beginning of the stunt was 55.0 m/s?

Can a satellite be in an elliptical orbit under uniform circular motion?

An ordinary car would not be able to go around an unbanked curve of a perfectly smooth road,no matter how the driver turned the wheels.

In uniform circular motion we have an acceleration and the speed doesn't change.But in projectile motion the speed does change under constant acceleration.Why are they both classified as uniform acceleration phenomena?

Orbiting satellites accelerate toward Earth at 9.8 m/s².

Satellites in orbit are accelerated toward Earth,so they must be getting closer and closer to our planet.

You are the science officer on a visit to a distant solar system.Prior to landing on a planet you measure its diameter to be 1.8 × 10⁷ m.You have previously determined that the planet orbits 2.9 × 10¹¹ m from its star with a period of 402 Earth days.Once on the surface you find that the acceleration due to gravity is 19.5 m/s².What are the masses of (a)the planet and (b)the star?