Physics (from Ancient Greek: φυσική (ἐπιστήμη), romanized: physikḗ (epistḗmē), lit. 'knowledge of nature', from φύσις phýsis 'nature') is the natural science that studies matter, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves.Physics is one of the oldest academic disciplines and, through its inclusion of astronomy, perhaps the oldest. Over much of the past two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the Scientific Revolution in the 17th century these natural sciences emerged as unique research endeavors in their own right. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in academic disciplines such as mathematics and philosophy.
Advances in physics often enable advances in new technologies. For example, advances in the understanding of electromagnetism, solid-state physics, and nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.
Homework Statement
[/B]
When a stream of air is directed over the end of a 40 cm long piece of plastic pipe, open at both ends, a sound is produced.
(a) Explain why this occurs
(b) If the bottom end of the pipe is covered, what will happen to the pitch of the sound? Explain
Homework Equations...
Homework Statement
In the diagram, m1 has a mass of 47 kg and m2 has a mass of 35 kg. The coefficients of friction between m1 and the surface of the inclined plane are µs = 0.42 and µk = 0.19.
(a) If the masses are held in place and then released, will they start to move?
(b) If the answer...
1. Determine the equation that represents the relationship between the power and the current when the electric potential difference is 24v and the resistance is 1.5 Ω. 2. Draw a graph of the parabola that corresponds to the equation found in (a). 3. Determine the current needed in order for...
Homework Statement
What is a situation where the efficiency of a device would change based on a redefinition of what is considered useful energy?[/B]Homework Equations
What would be considered useful energy?
How can the efficiency of a device change?[/B]The Attempt at a Solution
If heat or...
Homework Statement
An elevator takes a 70 kg person from street level to the top of a 400 m sky-scraper in 4 minutes. The mass of the elevator is 500 kg.
a] At what rate is the elevator plus the person gaining potential energy?
b] What power is the elevator plus the person experiencing as...
Okay. So I'm new to calculus. And this is the first time I'm solving a physics problem using integration.
I understood that ∫dt (or ∫1dt) will be equal to just 't+C.' (Just like f ' (t+C) = 1).
Though, that's not the problem. The problem is when I apply it this way:
Question: The expression for...
Homework Statement
A student pushes a 0.65kg box Ali g a desk. When he stops pushing the book, it moves 85cm before stoping (slowing down in this period). Coefficient of friction between book and Table is 0.27.Calculate the work done on the book by the friction. Should it be positive or...
Hi there, I am doing a physics assignment. I had to use a program called tracker to simulate the movement of a puck.
So I just need some help to see if anyone can figure out what I've done wrong as something isn't making much sense. Let's jump right into it.
When the puck moves down and hits...
I have to design a track for a skate boarder that is 50% efficient (friction must be present) from the start of the skater's drop-in, to his furthest point along the track.
My skater's mass will be 75kg
efficiency=energy output/energy input x100%
I am not really sure where to go next and how...
I am in search of physics textbooks which covers, basic kinematics, dynamics, rotational kinematics, rotational dynamics, gravitation and problems related to work and energy. I don't need theory. I prefer if the contains lots of exercise that are both difficult to solve as well as "concept...
Homework Statement
Driving along a steady speed of 26m/s and suddenly see a child 150m from you. Breaks can produce acceleration of -2.5m/s² but it takes time to get the foot from the gas to the brake pedal. How much time do you have, if to avoid hitting the child?
Known:
d=150m
a=-2.5m/s²...
Homework Statement
A puck of mass 30 g slides across rough ice, experiencing a frictional force of 0.20N. If it was moving at 10km/h when it hit the ice patch,
(a) how much time did it take to stop?
(b) how long was the ice patch?
Given:
m=30g (0.03kg)
Ff=0.20N
V=10km/h (2.7m/s)[/B]Homework...
Mod note: Moved from technical section, so no template
Question:
The ace Edward bow can shoot 182.8 meters at a 45 degree angle, it can shoot 12 arrow per minute.
What is the performance of the
Bow?
Attempt:
Basically considering the Dx=182.8 meters I assume the Dy is the same considering its...
Homework Statement
22. A 5.00 x 10^4 kg shuttle is orbiting the Earth 2.45 x 10^7 m above its surface. What is the Earth's gravitational field strength at this height.
a.)9.80m/s^2 b.) 1.29m/s^2
c.)0.418 m/s^2 d.)0.39m/s^2
23. What is the force of gravity between the shuttle and the...
Homework Statement
These are from a british columbia provincial exam from a few years ago. My teacher enlisted my help in trying to figure out a solution. This is supposed to be for physics 11.
I can't figure it out. Maybe one of you awesome people can help me. Thanks...
Question1.
A...
Homework Statement
A 5.0kg concrete block accelerates down a 34° slope at 4.2m/s^2. Find the coefficient of friction between the block and the slope.
Homework Equations
Fg=5*9.8=45
x=45sin30
y=45cos30
The Attempt at a Solution
a=(mgsinθ-Ff)/m → Ff=mgsinθ-ma
Thanks
1) Which is right?
65m/s x 3.2 s = 208 m
or
65m/s x 3.2 s = 2.1 x 10^1 m2) is 210 - 3 s.f. or 2 s.f. ?
3) my teacher uses the question as a guide for s.f., is that correct?
e.g. A projectile is fired with an initial speed of 1.12 s at a...
QUESTION 1
Homework Statement
A guitar string is 0.70m long and is tuned to play an E above middle C (330 Hz). How far from the end of this string must a finger be placed to play A above middle C (440Hz)
Homework Equations
\lambda = 2L/n
\lambda = v/f
v = \lambda x f
The...
Homework Statement
What is the relationship between the weight (N) vs mass (g)?
Homework Equations
The Attempt at a Solution
I am suppose to predict the relationship between the weight vs mass. I'm guessing it's directly proportional but I can't explain why in simple terms? I...
Homework Statement
A 3.0kg block of ice made in a fridge has an initial temp. of -5.0\circC. It
is then moved to a much colder freezer. how much thermal energy is released by the ice as it cools to -40.0\circC?
Homework Equations
EH = mc\DeltaT
for water, c = 4186 J/kg/\circC
The...
Homework Statement
A stone is thrown at 30 m/s. what is the widest river it can be thrown across? (the stones ends at the same vertical height from where it was thrown)
Homework Equations
x=vxot
y=vyot + 0.5gt2
The Attempt at a Solution
i know i need to find t first. using the...
Homework Statement
50N [S], 75N [N], 40N [W], and 55N [E] all act on a point. what is the resultant force?
Homework Equations
The Attempt at a Solution
I tried making w and s negative and n and e positive but that gave me 40N and the answer should be 29N, 59\circ N of E . help...
Physics 11 vector help please?
Homework Statement
A boy and a girl both swim at 1.5 m/s. they set out together to cross a river that is 50.0m across and has a current flowing south at 1.0m/s.the girl takes a heading so she'll travel straight east across the river. meanwhile, the boy maintains...
Homework Statement
A hot air balloon is carried by a wind with a velocity of 20 km/h [E]. If a passenger holds a flag out of the gondola, in what direction will the flag point?
Homework Equations
The Attempt at a Solution
The answer says down but idk why?
Physics 11 help please?!?
Homework Statement
a 1 200 kg car accelerates uniformly along level ground from rest to a speed of 80 km/h in 10 s. what is the power output of th motor?
Homework Equations
eff=(mgh/f*d)x100%
p=f*v
The Attempt at a Solution
idk where 2 start...
Physics 11 help??!
Homework Statement
a car jack applies a force of 3000N to lift one side of a car a distance of 10 cm. in order to accomplish this the person using the jack needed to apply a force of 1200N to the handle moving it 30 cm. what is the jack's efficiency?
Homework Equations...
Homework Statement
A pendulum bob is pulled sideways to the left. When released, the pendulum string will contact a horizontal rod causing the pendulum to swing in an arc of smaller radius.
the height to which the bob swings on to the right is equal to the original height but i don't...
Homework Statement
A 1.1 kg cart and a 2.2 kg cart are at rest with a compressed string between them. the force constant of the spring is 600 N/m. when the spring is released, the carts rapidly separate. how far must the spring have been compressed for the 2.2 kg cart to end up moving at 1.5...
Homework Statement
A spring can be compressed 12 cm by an applied force of 6.0 N. A 2.8 kg box sliding along a frictionless surface approaches this spring at a speed of 1.9 m/s. How far will the spring be compressed when the box comes to a stop?
Homework Equations
Ep = 0.5kx2
0.5mv2...
Homework Statement
A 1.0 kg block of wood is lifted a distance of 1.5 m from the floor and placed on a wooden shelf. A steady horizontal force is then applied to the block, causing it to slide sideways along the shelf a distance of 1.5 m at a uniform velocity. The kinetic coefficient of...
Homework Statement
A 15.0 g object initially moving to the right at 30.0 cm/s collides with a stationary 45.0 g object. After the collision the 45.0 g object is moving to the right at 15 cm/s.
what impulse does the 45.0 g object apply to the 15.0g object during collision?
Homework Equations...
Homework Statement
A 55 kg student wearing skates stands at rest on a frictionless horizontal ice surface. She throws a 10 kg backpack horizontally with a speed8.3 m/s [S].
What is the velocity of the student after she throws the backpack?
Homework Equations
F\Deltat = m\Deltav
The...
Physics 11 question -- its probs rly easy !
Homework Statement
A horizontal force applied to a 7.0 kg object initially at rest causes it to accelerate uniformly and travel a distance of 21m [s] in 4.2s. What is the change in momentum of the object?
Homework Equations
p = mv
The...
Homework Statement
g=10m/s^2
A fully loaded Saturn rocket has a mass of 2.92x10^6kg. Its engines have a thrust of 3.34x10^7N.
a) How much does the rocket weigh. answer 2.92x10^7 N
b) What is the net force on the rocket when it blasts off? answer 4.2x10^6N
c) What is the...
[SOLVED] Physics 11 Speed and acceleraton
Homework Statement
Linda sees an elephant dart into the road 50.0m ahead of her car while she is driving at 65km/hr. She slams on her brakes, which decelerate the car at the rate of -5.80m/s^2. Will she be able to avoid hitting the elephant? Find...
[SOLVED] Physics 11 Speed and acceleraton
Homework Statement
The brakes on a car permit it to decelerate at the rate of -8.0m/s^2. How much distance is required to stop this car when it is traveling 60.0km/hr?
The answer given is 173.6m
Homework Equations
A=V/T
D=RT
The...
Acceleration Question*URGENT* (Physics 11)
Okay well i have a test tomorrow and this is a question that was on my quiz, and i didnt know how to do this:
Homework Statement
1. A driver of a car going 90.0km/h suddenly sees a barrier 40.0m ahead. It takes the driver 0.75s before she applies...
Use the mirror equation to find the image location and the height of an object placed at the centre of curvature of a concave mirror. Also find the magnification. Hint: What is the relation between the focal length and the object distance, do, for this situation?
I'm really confused...
I have this project for Physics 11, we have to make some sort of optic device using our knowledge of concave/convec mirrors and lens. We have to make it and briefly describe and ****, it's due on friday and i haven't gotten anything. I was wondering if you guys know any good ideas or have a good...
Homework Statement
When a jet plane flies overhead at a high altitude, the sound from the engines can be heard, but the sound seems to come from well behind the aircraft. If you knew the altitude of the jet to be 10,000m, how could you estimate the speed of it? Show this using an...
Homework Statement
Magen's mass is 28kg. she climbs the 4.8m ladder of a slide and reaches a v3elocity of 3.2m/s at the bottom of the slide. How much work was done by friction on Magen
Homework Equations
Ep=mgh
Ek=1/2mv^2
W=Fd
The Attempt at a Solution
I really just have no...
Homework Statement
A 98N sack of grain is hoisted to a storage room 50m above the ground floor of a grain elevator.
a) how much work was required
b) what is the potential energy of the sack of grain at this height
c) the rope being used to lift the sack of grain breaks just as the sack...
Homework Statement
A constant net force of 410N up is applied to a stone that weighs 32N. The upward force is applied through a distance of 2.0m andthe stone is then released. TO what height from the point of release will the stone rise?
Homework Equations
Ep=mgh
The Attempt at a...
Hey if anyone could help me work through a couple of problems that would be great!:smile:
Homework Statement
It is not uncommon during the service of a professional tennis player for the racquet to exert an everage force of 150.0N on the ball. If the ball has a mass of 0.060kg and is in...
Homework Statement
An 845N sled is is pulled a distance of 185m. The taskt requires 1.20 x 10^4J of work and is done by pulling a rope with a force of 125N. At what angle is the rope held
Homework Equations
W=Cos(of theta) Fd
The Attempt at a Solution
F=845N
d=185m
W=1.20x10^4J...
Homework Statement
a 2575-kg van runs into the back of a 825-kg compact car at rest. they move off together at 8.5m/s. assuming no friction with the ground, find the initial speed of the van
This is really easy stuff, but I am really confused. I have a couple other questions as well. If there's anyone who's really good with momentum than do you think you could spend a little while to help me out? alright well here's one problem.
A 95kg fullback, running at 8.2m/s, collides in...
i was just wondering if anyone could help me work out this probelm? I've been having an extremely difficult time in physics. My teacher has only taught it once before and is difficult to understand. Anyways, here's the probelm. Three forces act simultaneously on point J. One force is 10.0 N...