Can you help me with this physics question?
The pendulum continues in an arc of reduced radius of L-D (L being the length of string).Okaay, so if it can get to the "highest point of the new reduced arc", let's write an energy balance for it: the starting energy (gravitational potential energy mgL) should equal the sum of kinetic energy and potential energy at the "highest point of the new reduced arc".mgL = 2mg(L-D) + 0.5 m v^2 (1) (2mg(L-D) because the ball rises to a height of 2(L-D) or twice the reduced radius)So if you want the D, you need the V. (I'm so sorry.) We can find v from the condition that D is the MINIMUM peg distance for which the string remains juuust taut, so in this limiting case, the tension in the string is juuust zero. Write a force balance for the ball when it is just at the "highest point of the new reduced arc" for this limiting case. Why, the only force seems to be gravity and the only acceleration of the ball is the centripetal acceleration. From Newton's law,m v^2/(L-D) = mg (centripetal acceleration is mv^2/r remember?)or, m v^2 = mg(L-D) (2)Substituting the above in Eqn. 1, mgL = 2.5 mg(L-D)or, D = 3/5 L Sic transit gloria mundi.
I need help with these physics questions pleasssee.?
with explanations please! as many as you can! 1)Concrete is sold by the cubic yard. What is the mass, in kilograms, of one cubic yard of concrete tha is 5x as dense as water? (1m = 1.094 yd, and 1m^3 of water has a mass of 1,000kg) 2) A car decelerates uniformly and comes to a stop after 10s. The car's average velocity during deceleration was 50 km/h What was the car's deceleration while slowing down? 3) A car traveling 60 km/h accelerates at the rate of 2.0 m/s^2. How much time is required for the car to reach a speed of 90 km/h? 4) An object is thrown upward with aspeed of 12 m/s on the surface of planet X wher the aceleration due to gravity is 1.5 m/s^2. What is the max height reached by the object? 5) A fighter plan moving 200 m/s horizontally fires a projectile with asped 50 m/s in a forward direction 30 degrees below the horizontal. What is the sped of the projectile with respect to astationary observer on the ground? 6) Your motorboat can move at 30 km/h in still water. How mcuh time wil it take u to move 12 km downstreat in a river flowing at 6 km/h? 7) A 10 kg box on a horizontal surface is pulled by a 5N force. A 3 N friction retards the motion. What is the acceleration of the object? 8) An object with mass m slides down arouch 37degree inclined plane whert he coefficient of kinetic friciton is .20. WHat's the accelerationof the object? 9)A roller coaster starts from rest at point 45m above the bottom of a dip neglect friction what wil be the speed of the roller coaster at the top of the next slope which is 30m above the bottom ofthe dip? 10) Two vectors A and B have components (0,1) and (-1,3) WHat is the magnitude of the sum of the two vectors? 11) A 1500kg car accelerates from 0 to 25 m/s in 7 s. What is the average power delivered by the engine? (1hp=746W)
Please help with these physics questions?
Hi, I got a homework from physics today and I didn't understand the teacher in the class. Can you guys please walk thorugh these problems with me... I put 3 for sample...(So I'm not asking you to do my whole homework for me..I'm just looking for a pattern in.) ---------- 1) A 4600 kg helicopter accelerates upward at 2.0 m/s ^ 2. What lift force is exerted by the air on the propellors? 2) The maximum force that a grocery bag can withstand ripping is 2250 N. Suppose that the bag is filled with 20 kg of groceries and lifted with an acceleration of 5.0 m/s ^ 2. Do the groceries stay in the bag? 3) A student, standing on a scale in an elevator at rest, sees that his weight is 840 N. As the elevator rises, his weight increases to 1050 N, then returns to normal. When the elevator slows to a stop at the 10th floor, his weight drops to 588 N, then returns to normal. Draw a motion map for the student during his elevator ride. Determine the acceleration at the beginning and end of the trip.
I need help with these two physics questions:?
1 The charge per unit length on a long, straight filament is 99 uC/m. Find the electric field 10.5 cm from the filament, where the distance is measured perpendicular to the length of the filament. Answer in units of N/C. 2 Consider a thin spherical shell of radius 15.4 cm with a total charge of 33.6 uC distributed uniformly on its surface. Find the electric field 9.4 cm from the center of the charge distribution. Answer in units of N/C.
Can anyone help me answer this physics question?
No, there is not enough information. The position the clown maintains in the air would change his air resistance and thus flight time and distance. However if you assume no air resistance, you can:resolve the vector for the vertical componant (sin23*51), to give the vertical speed initially,divide this value by the acceleration incurred by gravity (9.8ms^-2) and this will give you the time it takes for the vertical velocity to reach 0.Then you calculate the vertical distance travelled during this time (((initial vertical velocity+ final vertical velocity)/2)*time)((sin23*51+0)/2)*((sin23*51)/9.8)=d. This will give you the clowns height.Sub this value into (distance= initial velocity*time+1/2*acceleration*time^2), and hence using the vertical distancetravlled calculated in the previous step d=0*t+1/2*9.8*t^2, you can re-arrange to solve for t. (This should be equal to the value you obtained in step 2)Add the value of t to (sin23*51)/9.8 and you have the time spent in the air.Assuming no air resistance the horizontal speed does not change, so resolve for the vertical component (cos23x51) and multiply this by the time spent in the air and you have distance travelled from the canon.
Are the physics questions of the NEET tough?
No not at all. In my opinion I wouldn't hesitate from calling it easy. NEET physics is at a pretty basic level.Sadly most medical aspirants hate physics and tend to neglect it thinking that they would compensate in biology and chemistry. The end result is that their ranks take a huge blow. Let me tell you that physics will be the deciding factor of your NEET rank.Now coming to how to prepare for it? Most aspirants make a mistake of referring to too many books for Physics which are beyond the scope of NEET syllabus. My advice is that you stick to your NCERT syllabus. Always refer NCERT first for your concept building. After going through a concept immediately go through mcqs related to that topic given in your coaching centre material, mock exams and past papers. Pay particular attention to numerical based problems as this is where many students fail. Physics requires extensive practice to perfect so go through all kinds of mcqs related to NCERT concepts. If you practice well enough then you will surely be satisfied with your physics performance. Believe me NEET physics is a cakewalk if you practice the right way.
`pls i need help on these physics questions (1) A uniform beam of 20gram and length 120cm rest horizontally on
Weight of beam = 0.02*9.8= 0.196 N, and the center of gravity is 0.6 meter from A Since beam is in equilibrium, then The sum of all forces are 0, and the sum of all moments about any point are 0. 0.196 = R+S S = (0.196-R) The moment about point A = 0; let the counter clock wise moment = positive! R* 0.2 + S*0.8 = 0.196*0.6 = 0.1178 Substitute the value of S from the first equation R*0.2 +(0.196-R)*0.8= 0.1178; 0.2R +0.1568 -0.8*R = 0.1178 2R + 1.568 -8R = 1.178 -6R= 1.178-1.568 6R = 0.39 R= 0.065N S = 0.196-0.065=0.131N S+R= 0.196. The values confirm Placing 10 kg on the beam a distance = X meter from A to equalize the forces on R and S, we must satisfy the following equation: 2R = 10.02 R* 0.2 + R*0.8 = 10.02*9.8*X =98.196*X 20R + 80R = 9819.6* X 100R = 9819.6*X X = (100R/9819.6) 2R = 10.02 R= 10.02/2=5.01 X= (100*5.01)/9819.8 X = 501/9819.8 X= 0.05102 meter from A; or 5 .01 cm fro point A which exists at the left end of the beam Hope to have helped! The values are correct God Bless!
Help on these physics questions please.
A) An airplane travels 2100 km at a speed of 1000 km/h. It then encounters a headwind that slows it to 800 km/h for the next 1300km. What was the average speed of the plane for this trip. B) Two locomotives approach each other on parallel tracks. Each has a speed of 120 km/h with respect to the earth. If they are initially 8.5 km apart, how long will it be before they pass each other?
Need help with these last physics questions please. thank you :)?
Objects acquire a charge through the transfer of: Neutrons Protons Electrons Photons 2: The weight of an object depends on _______ and the ______ of the object. Acceleration due to gravity, velocity Acceleration due to gravity, mass Velocity, position Velocity, charge 3: Two charges are separated by 3.0 cm. Object A has a charge of +6.0 micro-coulombs and object B has a charge of +3.0 micro-coulombs. What is the force on object A? 2.6 x 102 N in the x direction 2.6 x 102 N in the y direction 1.8 x 102 N in the x direction 1.8 x 102 N in the y direction 4: Which has the lowest energy? Ultraviolet rays Gamma rays Radio waves X-rays 5: In a parallel circuit, five resistors of values 20 ohms, 15 ohms, 5 ohms, 35 ohms, and 25 ohms are considered. What is the equivalent resistance of the entire circuit? 2.6 ohms 0.8 ohms 0.4 ohms 1.3 ohms 6: The sum of the electric potential difference around a closed loop circuit is zero. This is called: Ohm’s law Kirchoff’s voltage law Coulomb’s law Newton’s 2nd law 7: Absolute zero is also: 0 F 0 C -273.15 C -273.15 F 8: The rate of doing work is called: Force Velocity Current Power 9: In a series circuit, four resistors of values 75 ohms, 10 ohms, 20 ohms, and 15 ohms are considered. What is the equivalent resistance of the entire circuit? 210 Ohms 2.25 x 105 Ohms 60 Ohms 120 Ohms 10: A punter whishes to kick a ball as far as he can. His kick should be closest to what angle to achieve this: 30o 45o 60o None of the above
Can solving questions in physics help clear the NEET?
Physics is a subject, which can turn out to be the most scoring section, if understood well. The most important aspect in learning physics is understanding the concepts well. So always keep in mind, keep your CONCEPTS CLEAR.I would recommend you to start your chapter/topic from NCERT. Go through the theory part, understand it well. Highlight the points you think are important. Also mark the areas where you think you are lacking and need further clarification. Clear your doubts from your tutor. If not, surf the internet. You will definitely get some clue. Then attempt the solved and unsolved question of that chapter. The “Summary” and “Points to Ponder” section are very important for the ASSERTION REASON questions in AIIMS.After this move on to HC Verma, Arihant DC Pandey, or your Coaching Institute Material/Booklets(if any). Attempt as many question possible from these resources to get an idea of JEE level questions. HC Verma is a legendary book for preparing Physics for competitives.After completion of the above, move on to Previous Year Questions. Attempting and solving previous year questions is very important to get an idea of what kind of questions are asked in NEET.If you have done all of the above and feel confident about yourself, attempt a mock test on the chapters you have learnt in a stipulated time, say a month.Few more points to remember:Give a lot of time to Mechanics, especially Work Power Energy and Rotation. This is the section which could fetch you 100% score if understood well.You need to practice Mechanics repeatedly and don't lose your concepts. Mechanics need to be revised at least 3 times.Modern Physics is a very easy but conceptual section. Read it thoroughly both from NCERT and HC Verma. Mostly formula based questions are asked from this area.Optics is also a very easy section. Memorise all the formulas and know their right implementation on different types of question.Magnetics, Electrostatics can be a little complicated and confusing. Practice it well!!Memorize the range and frequency of each kind of wave in Electromagnetic Wave chapter well.Always keep brushing up on your concepts, or else you will forget it sooner or later.