Madie

The small spherical planet called "Glob" has a mass of 8.10×10^18kg and a radius of 6.20×10^4m. An astronaut on the surface of Glob throws a rock straight up. The rock reaches a maximum height of 1.80×10^3m above the surface of the planet before it falls back down. What was the initial speed of the rock as it left the astronaut's hand? (Glob has no atmosphere, so no energy is lost to air friction.) 6.67E-11Nm2/kg2.

I get 24.97 but that's not right

1. A box of mass m hangs by a string from the ceiling of an elevator that is accelerating upward.

1a. Which of the following best describes the tension T in the string?

T < mg

T = mg

T > mg

1b. Briefly explain your answer to the previous question.

2. A box of mass m is hung by a spring from the ceiling of an elevator. When the elevator is at rest, the length of the spring is L = 1m.

2a. As the elevator accelerates upward, the length of the spring will be

L < 1 m

L = 1 m

L > 1 m

2b. Briefly explain your answer to the previous question.

*the following are multi-choice questions then to explain reasoning behind them*

1a. The net force on a box is in the positive x direction. Which of the following statements best describes the motion of the box?

-Its velocity is parallel to the x axis.

-Its acceleration is parallel to the x axis.

-Both its velocity and its acceleration are parallel to the x axis.

-Neither its velocity nor its acceleration need to be parallel to the x axis.

1b. explain your reasoning from above

2. You are driving a car around a circular track.

2a. The net force acting on your car...

-Points radially inward, toward the center of the track.

-Points radially outward, away from the center of the track.

-Points forward, in the same direction you are moving.

-Points backward, opposite to the direction you are moving.

-Is zero.

2b. The momentum of your car...

-Points radially inward, toward the center of the track.

-Points radially outward, away from the center of the track.

-Points forward, in the same direction you are moving.

-Points backward, opposite to the direction you are moving.

-Is zero.

2c. explain your reasoning for the above two questions

1. x^3 - 3x^2 - 6x + 8 = 0

2. cos(x) * (x^2 - 25) = 0

3. sin(3x) * (x^3 + 3x^2 - 16x - 48) = 0

An object is moving in a straight line with a constant acceleration. Its position is measured at three different times, as shown in the table below.

Time (s) Position, (m)

58.70 9.800

60.10 17.465

61.50 31.500

Calculate the magnitude of the acceleration at t=60.10s.

I got 3.1557 m/s/s but that is wrong. please help

my friend asked me this. i am kinda curious too

why is an inbox called an inbox? it isn't really a box. i'm sure there is a reason for it. any insights?

one of my friends asked what a heartless boob grabber was. even though its kinda self explanatory, he wants to know what it is