physics

If a more efficient exhaust system design doubles the exhaust velocity of only the third stage of our rocket. what will be the top speed of the payload riding on top of the whole space vehicle?

11,500 4500 x 2 = 9000 9000 + 2000 + 500

The moon has no atmosphere, so it is possible to orbit a satellite just above the peak of the tallest lunar hill. the gravity at its surface is 1/6th the earths surface gravity. the radius of the moon is 1740km. what horizontal velocity must a satellite have to skim the lunar surface in circular orbit?

1685 m/s 9.8 x 1/6th = 1.633 1.633 x 1740000 = 2842000 square root of 2842000

if the earth doubled in mass but stayed the same size, what would be the acceleration due to gravity at the surface?

19.6 m/s2 9.8 x 2

The brake system in most cars makes use of a hydraulic system. this system consists of a fluid filled tube connoted at each end to a piston. assume the piston attached to the brake pedal has cross sectional area of one square centimeter and the piston attached to the brake pad had a cross section of two square centimeters. when you apply a force of 10 newtons to the piston attached to the brake pedal, the force at the brake pad will be

20 newtons

what is the force exerted on the satellite in orbit by the earth

227 N 6.67e11 x (1000)(6e24) divided by (42000000)2 g x mme / r squared

What wis the magnitude of the static water pressure you will observe on a pressure gauge connected to a water main at street level if the municipal water system is supplied by a water tower 25m tall

245,000 pa 25 x 1000 x 9.8

very big and very small numbers are conveniently written in scientific notation. what are the correct notation versions of 33.33 and -2,100

3.333e1 and -2.1e3

if the water pressure on the first floor of gosnold hall is 1000000 pascals what is the greatest velocity that water can attain when it sprays out of a hose connected to the building

44.7

A three stage rocket is often used to launch space vehicles. the first stage is capable of accelerating from zero to 500 m/s when burdened with both upper stages and the payload. the second stage can accelerate from zero to 2000 m/s when carrying the payload and the third stage. the small third stage can accelerate the payload from zero to 4500 m/s. how fast will the payload be traveling when all three rockets have expended their fuel?

7000 m/s 500 + 2000 + 4500

what was the force of gravity exerted on the same satellite when it sat on the launch pad in florida

9,800N F=MA 1000 x 9.8

a toy company specializing the alaska market makes a water rocket wutg a 0.1kg body that contains 0.9kg water as ice. it uses air pressure to eject the ice as a single chunk at 10m/s when the rocket is launched. what is the initial velocity of the plastic body when it is launched horizontally across the class room?

90 m/s -9 divided by 0.1

physics terms are often incorrectly used in the popular press. identify the error in this statement from the discovery channel: hero mike rowe is afraid of a shark that can bite with a force of 2000 pounds per square inch

Bite force should be specified in pounds, not pounds per square inch

although a perfectly smooth golf ball...

a reduced sideways curving flight

who wrote our text how things work

bloomfield

the fastest types of racing cars, formula 1 and indy cars, have wings attached to them to increase the downward force on their wheels and thus increase traction. the wings generate

both drag and lift

which fundamental law of physics provides the primary basis for bernoullis principle that pressure and velocity can be exchanged in a flowing fluid

conservation of energy

we know that high quality gold jewelry will be

denser

the most effective stroke in tennis is the top spin lob, in which the top of the ball spins away from the player who hit it. which way is the lift force on this ball directed

downward

which of these men was not involved in the discovery of the motions of the planets

ferguson

doubling the flow velocity in a water pipe will increase the kinetic energy of the stream by what factor?

four times

the maximum speed of a practical single stage rocket can achieve is

greater than the speed of its exhaust plume but less than is required for most satellite launches

when one of the f-22 raptors launches a missile, what does the missile push against to accelerate away from the plane?

its own exhaust

which temperature scale has 373 degrees as the boiling point of water

kelvin

a curve ball in baseball curves because of

lift forces

Do it yourself car wash on route 17 you can have 3 minutes of spray to clean your vehicle. what is the pressure of the water when it hits your fender?

one atmosphere (100,000 spa)

to make an airplane fly upside down the pilot must

point the nose of the plane slightly up to create a positive angle of attack on the wrong side of the wing

you are floating along in a hot air balloon. you look up and notice that the bottom of the balloon is open. Although there is a minor loss of hot air due to the diffusion of molecules the majority of the hot air remains inside the balloon despite this opening because

the air pressure in the balloons opening is the same as the air pressure outside that opening

an astronaut is in orbit in the international space station. which of the following statements is true?

the astronaut feels weightless because both she and the station are accelerating at the same rate

why does a tennis ball not slow down very quickly when hit

the fuzz causes turbulence that energizes the boundary layer of air

pure turbo engines are fuel hogs compared to propellers because

the jet imparts a bigger velocity change to a smaller mass flow of air to generate thrust

the magnetite of the gravitational force the earth exerts on the moon is __________ the magnitude of the force that the moon exerts on the earth

the same as

the driver of a ski boat can feel the effect of the skiers antics. when the skier turns hard to left or right. the boat slows down slightly because

the skier increased his drag when he generated the lift needed to accelerate him from side to side

when your house was new the clean copper pipes could deliver a generous flow of water to the shower. A decade later calcium deposits have reduced the inside diameter of the pipes and the shower feels weaker because

the water must flow faster through the smaller opening in the pipe. since it has more kinetic energy it has less available pressure potential energy to drive the shower

archimedes principle states that the buoyant force exerted by a fluid on an object wholly of partially immersed in it is equal to

the weight of the fluid displaced by the object

why does the from edge of a boeing 737's wing have a row of very small fins sticking straight up from the otherwise smooth surface

to energize slow moving the boundary layer and delay flow separation from the wing

commercial airliners are predominantly powered by

turbo fan engines