carolynn armstrong
2022-07-19

You can still ask an expert for help

asked 2021-01-13

A radar station, located at the origin of xz plane, as shown in the figure , detects an airplane coming straight at the station from the east. At first observation (point A), the position of the airplane relative to the origin is $\overrightarrow{{R}_{A}}$. The position vector $\overrightarrow{{R}_{A}}$ has a magnitude of $360}^{m$ and is located at exactly $40}^{\circ$ above the horizon. The airplane is tracked for another $123}^{\circ$} in the vertical east-west plane for $5.0}^{s$, until it has passed directly over the station and reached point B. The position of point B relative to the origin is $\overrightarrow{{R}_{B}}$ (the magnitude of $\overrightarrow{{R}_{B}}$ is $880}^{m$). The contact points are shown in the diagram, where the x axis represents the ground and the positive z direction is upward.

Define the displacement of the airplane while the radar was tracking it: ${\overrightarrow{R}}_{BA}={\overrightarrow{R}}_{B}-{\overrightarrow{R}}_{A}$. What are the components of ${\overrightarrow{R}}_{BA}$

Express ${\overrightarrow{R}}_{BA}$ in meters as an ordered pair, separating the x and z components with a comma, to two significant figures.

asked 2021-05-04

Until he was in his seventies, Henri LaMothe excited audiences by belly-flopping from a height of 13 m into 35 cm. of water. Assuming that he stops just as he reaches the bottom of the water and estimating his mass to be 72 kg, find the magnitudes of the impulse on him from the water.

asked 2021-01-19

In a truck-loading station at a post office, a small 0.200-kg package is released from rest a point A on a track that is one quarter of a circle with radius 1.60 m.The size of the packageis much less than 1.60m, so the package can be treated at aparticle. It slides down the track and reaches point B with a speed of 4.80 m/s. From point B, it slides on a level surface a distanceof 3.00 m to point C, where is comes to rest.

(a) What is the coefficient of kinetic friction on the horizontal surface?

(b) How much work is done on the package by friction as it slides down the circular arc from A to B?

asked 2020-12-05

A diving borad 3.00 m long is supported at a point 1.00 m fromthe end, and a diver weighing 500 N stands at the free end. The diving board is of uniform cross section and weighs 280N.

A. Find the force at the support point.

B. Find the force at the end that is beng held down.

asked 2021-01-15

An airplane starting from airport A flies 300 km east, then 350 km at 30 degrees west of north and then 150 km north to arrive finally at airport B. The next day, another plane flies directly from A to B in a straight line. In what direction should the pilot travel in this direct flight? How far willthe pilot travel in the flight? Assume there is no wind during either flight.

asked 2022-07-24

asked 2022-10-02

Rewrite cot(cos^-1 6u) as an algebraic expression in u.