



Newton’s second law of motion is more than a definition; it is a relationship among acceleration, force, and mass. It can help us make predictions. Each of those physical quantities can be defined independently, so the second law tells us something basic and universal about nature. The next section introduces the third and final law of motion.
Section summary
Conceptual questions
(a) Give an example of different net external forces acting on the same system to produce different accelerations. (b) Give an example of the same net external force acting on systems of different masses, producing different accelerations. (c) What law accurately describes both effects? State it in words and as an equation.
Got questions? Get instant answers now!
The gravitational force on the basketball in
[link] is ignored. When gravity
is taken into account, what is the direction of the net external force on the basketball—above horizontal, below horizontal, or still horizontal?
Got questions? Get instant answers now!
Problem exercises
You may assume data taken from illustrations is accurate to three digits.
If the sprinter from the previous problem accelerates at that rate for 20 m, and then maintains that velocity for the remainder of the 100m dash, what will be his time for the race?
Got questions? Get instant answers now!
Questions & Answers
is there a formula for magnitudes of displacement
A Body of maas m slides down an incline and reached the bottoms with a velocity v
mass is the amount of matter a body contains.
prakash
When using the Conservation of Energy equation, do we substitute the energy as a negative quantity when the energies on a single object are exerting forces opposite to one another?
Ex. On an inclined plane, gravitational potential energy, friction energy/work and spring potential energy. (Let's say that the spring is keeping the box from sliding down the slope.) How do we use this in the equation? I'm so confused
Jennifer
Oh! And if there's kinetic energy that is exerting a force opposite to the spring, what do we do?
Jennifer
Then we subtract the k.e. from force exerted from newton's 2nd law.
Prem
Subtract energy from force? They're different units
Jennifer
why is it dat when using double pan balance
the known and unknown mass are the same
discuss the uses of energy in the following sectors of economy security and education
amajuoyi
why the current produce during dc motot is not use for its working rather we have to supply current outside
Tanveer
is there more then 4 dimensions
hello I kinda need help in physics... a lot
Brown
Brown. what kind of help
Jeff
when it comes to physics stick with the basics don't overthink things
Jeff
sticking to the basics will take you farther than overwhelming yourself with more than you need to physics is simple keep it simple
Jeff
for real....?
so I've got to know the fundamentals and use the formula to solve any problem
Brown
read Stephan hawkings a brief history of time
ayesha
it'll help you understand better than summing up formulas or ready textbooks
ayesha
physics isn't hard it's just understanding and applying the formulas if u need help ask any question
ayesha
okay...because I've got an exam next year February a Computer based exam
Brown
start with a pace a plan and stick to it
ayesha
well best of luck can't help you much there contact your teachers for tips and helpful notes
ayesha
how can we find absolute uncertainty
the basic formula is uncertainty in momentum multiplied buy uncertainty In position is greater than or equal to 4×pi/2. same formula for energy and time
Luke
I have this one question can you please look it up it's 9702/22/O/N/17
Question 1 B 3
ayesha
would you like physics?
Suthar
precision or absolute uncertainty is always equal to least count of that instrument
Iram
how do I unlock the MCQ and the Essay?
what is the dimension of strain
Is there a formula for time of free fall given that the body has initial velocity? In other words, formula for time that takes a downwardshot projectile to hit the ground. Thanks!
What is unit of watt?
Kulsum
watt is the unit of power
Rahul
watt can also be expressed as Nm/s
Rahul
what s i unit of mass
Maxamed
SI unit of mass is Kg(kilogram).
Robel
what is formula of distance
Maxamed
Formula for for the falling body with initial velocity is:v^2=v(initial)^2+2*g*h
Mateo
i can't understand
Maxamed
we can't do this calculation without knowing the height of the initial position of the particle
Chathu
sorry but no more in science
Imoreh
2 forces whose resultant is 100N, are at right angle to each other .if one of them makes an angle of 30 degree with the resultant determine it's magnitude
50 N... (50 *1.732)N
Sahim
Plz cheak the ans and give reply..
Sahim
50 N...(50 *1.732)N
Ibrahim
what is the value of f1 and f2
Syed
what is the value of force 1 and force 2.
Syed
Is earth is an inertial frame?
The abacus (plural abaci or abacuses), also called a counting frame, is a calculating tool that was in use in Europe, China and Russia, centuries before the adoption of the written Hindu–Arabic numeral system
Sahim
Is earth inertia frame?
Sahim
What is an abucus?
Irungu
what would be the correct interrogation "what is time?" or "how much has your watch ticked?"
someone please give answer to this.
prakash
time is the distance measured on clock
KINGSFORD
time is that in which events are distinguishable with reference to before and after
Omo
time measure of duration interval of period
Sewmeho
a load of 20N on a wire of cross sectional area 8×10^7m produces an extension of 10.4m. calculate the young modules of the material of the wire is of length 5m
Young's modulus = stress/strain
strain = extension/length (x/l)
stress = force/area (F/A)
stress/strain is F l/A x
El
Source:
OpenStax, College physics. OpenStax CNX. Jul 27, 2015 Download for free at http://legacy.cnx.org/content/col11406/1.9
Google Play and the Google Play logo are trademarks of Google Inc.