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Prove that newton's second law of motion is the real law
Fuel is consumed at the rate of 50kg/s in a rocket.The exhaust gases are ejected at a speed of 10km/s with respect to the rocket.What is the thrust experienced by the rocket?Also calculate the acceleration of the rocket at the instant when the mass is reduced to 5000kg .Take initial velcity to be zero.
State and prove law of conservation of linear momentum
Friction is a necessary evil.Explain
State and prove the conservation of angular momentum.
in formula F=DP/DT, d stands for what?
A particle of mass m moves with constant speed v on a circular path of radius r. Find the magnitude of average force on it in half revolution.
Two balls A and B are thrown simultaneously ,A vertically upwards with a speed of 20m/s from ground,and B vetically downwards from a height of 40 m with the same seed and along the same line of motion . At what points do the two balls collide ?
A cricket ball of mass 150g is moving with a velocity of 12m/s and is hit by a bat, so that the ball is turned back with a velocity of 20m/s. The force of the blow acts for 0.01s on the ball. Find the average force exerted by the bat on the ball.
what are the limitations of dimensional analysis?
If y = 3x square -2x + 1, find the value of x for which dy/dx =0.
A machine gun has a mass of 20kg. It fires 30g bullets at the rate of 400 bullets per second with a speed of 400 m/s. What force must be applied to the gun to keep it in position ?
show that for two complementary angles of projection of a projectile thrown with thw same velocity. the horizontal ranges are equal
prove Lami's theorem.
a block A of mass4 kg is placed on another block B of mass 5kg B rests on smooth table for sliding block A onB a horizontal force of 12 N is required to be applied on A how much max force can be applied on Bso that both A andB move together
Question: On an object of mass 1 kg moving along x-axis with constant speed 8m/s, a constant force 2 N is applied in positive y- direction. Find its speed after 4 seconds.
Please explain how to solve the above question. The answer is 8√2m/s.
a block of mass m is placed on a smooth wedge of inclination theta.the whole system is acclerated horizontally so that the block has a magnitude equal to???
A Spring Of Force Constant k is cut into two pieces , such that one piece is doubled the lengthof other . Then the long piece will have a constant of...................?
why cricket player lowers his hands while catching a cricket ball?
ABCDEF is a regular hexagon,,, Prove that AB + AC + AD + AE + AF = 6AO.
(direction sign {--} is present on the top of AB , AC,AD,AE,AF and 6AO)
derive an expression for banking of road with the help of diagram?
why wheels are made circular in automobiles?
Why is pulling a lawn roller easier than pushing it?
a stone is dropped from a height h . it hits the ground with a certain momentum P . if the same stone is dropped from a height 100% more than the previous height , the momentum when it hits the ground will change by ??
In a pickup game of dorm shuffleboard,students crazed by final exams use a broom to propel a calculus book along the dorm hallway. If the 3.5 kg book is pushed from rest through a distance of 0.90 m by the horizontal 25 N force from the broom and then has a speed of 1.60 m/s,what is the coefficient of kinetic friction between the book and the floor?
How is a friction is a necessary evil?
Q=A ball of mass 20 g hits a wall at an angle of 45o with a velocity of 15 m/s.If the ball rebound at 90o to the direction of incidence ,calculate the impulse received by the ball.
define angle and coefficient of friction and find the relationship b/n them.
A man falls on a cemented floor and a man falls on a heap of sand who will get more hurt & why?
1. A block of mass 10kg is sliding on a surface inclined at a angle of 300 with the horizontal. Calculate the acceleration of the block. The coefficient of kinetic friction between the block and the surface is 0.5?
how to solve this question with figure 3 blocks r connected together like on a horizontal frictionless table pulled to right with a force=50n if m1=5kg, m2=10kg, m3=15kg. find tension t1 and t2.
2. two masses of 7kg and 12kg r connectd at two end of light inextinsible string that goes over frictionless pulley. find acceleration of mass and tension on the string
prove that impulse is equal to the change in momentum
why friction is called a necessary evil?
what is normal reaction force?
the motion of a particle of mass m is described by y = ut + 1/2 gt2 . find the force acting on the particle
1. prove that angle of repose is equal to angle of friction
2. prove that 2nd law of motion is the real law of motion. (what is real law of motion)
state the triangle law of vector addition and the parallelogram law of addition of vectors.
Two blocks of masses 2 kg. and 1 kg. are in contact with each other on a frictionless table . When a horizontal force of 3 N is applied to the block of mass 2 kg. the value of the force of contact between the two block is :
(1) 4 N (2) 3N (3) 5 N (4) 1 N
a circular race track of radius 300 m is banked at an angle of 150. if the coefficient of friction between the wheels of a race car and the road is 0.2 , what is the (i) optimum speed of the race car to avoid wear and tear on its tyres (ii) maximum permissible speed to avoid slipping ?
plz experts help me out..............
a block of mass 2 kg rests on a rough inclined plane making an angle 30degrees with the horizontal . the coeffecient of static friction between the block and the plane is 0.7 . the frictional force on the block is??
a body constrained to move along the z axis of a coordinate system is subjected to a constant force F = ( -i +2j +3k) N . what is the work done by the force in moving the body over a distance of 4 m along the z axis.
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Syllabus
Prove that newton's second law of motion is the real law
Fuel is consumed at the rate of 50kg/s in a rocket.The exhaust gases are ejected at a speed of 10km/s with respect to the rocket.What is the thrust experienced by the rocket?Also calculate the acceleration of the rocket at the instant when the mass is reduced to 5000kg .Take initial velcity to be zero.
State and prove law of conservation of linear momentum
moving down with a uniform acceleration
of 5ms^ -2, what will be the apparent weight
of the child?
Friction is a necessary evil.Explain
A child is sitting inside a lift in a multi-storey
building.
What will happen to the weight of the
child if?
i. The lift moves up with a
constant speed?
ii. The lift moves up with a
constant acceleration?
b) Write down expressions for the
apparent weight felt by the child when the
lift is:
i. ascending.
ii. Descending with a uniform
acceleration
State and prove the conservation of angular momentum.
in formula F=DP/DT, d stands for what?
A particle of mass m moves with constant speed v on a circular path of radius r. Find the magnitude of average force on it in half revolution.
1.the fraction remaining after 5000 days
2. the activity of the sample after 5000 days
Two balls A and B are thrown simultaneously ,A vertically upwards with a speed of 20m/s from ground,and B vetically downwards from a height of 40 m with the same seed and along the same line of motion . At what points do the two balls collide ?
A cricket ball of mass 150g is moving with a velocity of 12m/s and is hit by a bat, so that the ball is turned back with a velocity of 20m/s. The force of the blow acts for 0.01s on the ball. Find the average force exerted by the bat on the ball.
a) the time of take off
b) acceleration
c)thrust of the jet engine
d) impulse
e) momentum at take off
what are the limitations of dimensional analysis?
If y = 3x square -2x + 1, find the value of x for which dy/dx =0.
A machine gun has a mass of 20kg. It fires 30g bullets at the rate of 400 bullets per second with a speed of 400 m/s. What force must be applied to the gun to keep it in position ?
1) how far will the barge move?
2) if the man walks at an average velocity of 8m/s,what is the average velocity of the barge?
(A) F (B) 2F (C) F/3 (D) 3F/2
28. If pulleys shown in the diagram are smooth and massless and a 1 and a2 are acceleration of blocks of mass 4 kg and 8 kg respectively, then
(a) a1 = a2
(b) a1 = 2a2
(c) 2a1 = a2
(d) a1 = 4a2
show that for two complementary angles of projection of a projectile thrown with thw same velocity. the horizontal ranges are equal
prove Lami's theorem.
a block A of mass4 kg is placed on another block B of mass 5kg B rests on smooth table for sliding block A onB a horizontal force of 12 N is required to be applied on A how much max force can be applied on Bso that both A andB move together
Question: On an object of mass 1 kg moving along x-axis with constant speed 8m/s, a constant force 2 N is applied in positive y- direction. Find its speed after 4 seconds.
Please explain how to solve the above question. The answer is 8√2m/s.
falls with his head forward. What should he
do in order to land safely
a block of mass m is placed on a smooth wedge of inclination theta.the whole system is acclerated horizontally so that the block has a magnitude equal to???
3. The breaking strength of the string connecting wall and block B is 175N, find the maximum magnitude of weight of block A for which the system will be stationary. The block B weighs 700 N (neglect friction)
(g = 10 m/s2)
A Spring Of Force Constant k is cut into two pieces , such that one piece is doubled the lengthof other . Then the long piece will have a constant of...................?
(A) m
(B) 2m
(C) 2.5m
(D) 3m
why cricket player lowers his hands while catching a cricket ball?
ABCDEF is a regular hexagon,,, Prove that AB + AC + AD + AE + AF = 6AO.
(direction sign {--} is present on the top of AB , AC,AD,AE,AF and 6AO)
derive an expression for banking of road with the help of diagram?
why wheels are made circular in automobiles?
(1) 1 m/s2 (4) 3 m/s2 (3) 4 m/s2 (4) 2 m/s2
1) 10root3 m /s
2) 20root m/s
3) 40/root3 m/s
4) 40 m/s
Why is pulling a lawn roller easier than pushing it?
a stone is dropped from a height h . it hits the ground with a certain momentum P . if the same stone is dropped from a height 100% more than the previous height , the momentum when it hits the ground will change by ??
In a pickup game of dorm shuffleboard,students crazed by final exams use a broom to propel a calculus book along the dorm hallway. If the 3.5 kg book is pushed from rest through a distance of 0.90 m by the horizontal 25 N force from the broom and then has a speed of 1.60 m/s,what is the coefficient of kinetic friction between the book and the floor?
How is a friction is a necessary evil?
trajectory it splits into three segments of masses m, m and 2m. First part falls vertically
downward with zero initial velocity and second part returns via same path to the point of
projection. The velocity of third part of mass 2m just after explosion will be
a) U cos theta b) 3/2 u cos theta c) 2u cos theta d) 5/2 u cos theta
(A) 500 N (B) 400 N (C) 670 N (D) 300 N
with outer edge raised to make 5 degrees with
the horizontal.
Calculate the permissible speed of the car
if the coefficient of friction is 0.2.
Q=A ball of mass 20 g hits a wall at an angle of 45o with a velocity of 15 m/s.If the ball rebound at 90o to the direction of incidence ,calculate the impulse received by the ball.
define angle and coefficient of friction and find the relationship b/n them.
Force is applied on an object of mass 2 Kg at rest on a frictionless horizontal surface as shown in the graph. The speed of the object at t=1 s will be
(1) 7.5 m/s (2) 12.5 m/s
(3) 10 m/s (4) 25 m/s
A man falls on a cemented floor and a man falls on a heap of sand who will get more hurt & why?
1. A block of mass 10kg is sliding on a surface inclined at a angle of 300 with the horizontal. Calculate the acceleration of the block. The coefficient of kinetic friction between the block and the surface is 0.5?
how to solve this question with figure 3 blocks r connected together like on a horizontal frictionless table pulled to right with a force=50n if m1=5kg, m2=10kg, m3=15kg. find tension t1 and t2.
2. two masses of 7kg and 12kg r connectd at two end of light inextinsible string that goes over frictionless pulley. find acceleration of mass and tension on the string
prove that impulse is equal to the change in momentum
(b) A Diwali rocket is ejecting 0.04 kg of gases per second at a speed of 400 m/s. What is the accelerating force on the rocket?
why friction is called a necessary evil?
what is normal reaction force?
the motion of a particle of mass m is described by y = ut + 1/2 gt2 . find the force acting on the particle
a) 12 m/s2
b) 4 m/s2
c) 10 m/s2
d) Zero
1. prove that angle of repose is equal to angle of friction
2. prove that 2nd law of motion is the real law of motion. (what is real law of motion)
state the triangle law of vector addition and the parallelogram law of addition of vectors.
Two blocks of masses 2 kg. and 1 kg. are in contact with each other on a frictionless table . When a horizontal force of 3 N is applied to the block of mass 2 kg. the value of the force of contact between the two block is :
(1) 4 N (2) 3N (3) 5 N (4) 1 N
a circular race track of radius 300 m is banked at an angle of 150. if the coefficient of friction between the wheels of a race car and the road is 0.2 , what is the (i) optimum speed of the race car to avoid wear and tear on its tyres (ii) maximum permissible speed to avoid slipping ?
plz experts help me out..............
A body is initially at rest.A net force F acting on it varies with time.Then prove that the body can not remain at rest.
a block of mass 2 kg rests on a rough inclined plane making an angle 30degrees with the horizontal . the coeffecient of static friction between the block and the plane is 0.7 . the frictional force on the block is??
46. The speed-time graph for the motion of a motorcycle is shown here. What is the average speed over 12 s interval ?
A. 4.38 m s-1
B. 5.58 m s-1
C. 1.75 m s-1
D. 3.17 m s-1
a body constrained to move along the z axis of a coordinate system is subjected to a constant force F = ( -i +2j +3k) N . what is the work done by the force in moving the body over a distance of 4 m along the z axis.
(A) = mg sec , = reaction force between wedge and sphere
(B) F = mg tan
(C) = mg tan , = reaction force between sphere and vertical wall
(D) = Mg + mg; = reaction force between ground and wedge
a lift which is moving vertically downwards
with an acceleration of 1.8 m/s2
a) Will the passenger experience
decease or an increase in his weight/
Explain?
b) What will be the effect if the cable is
cut and the lift falls freely?
a) 760 N
b) 1360 N
c) 1580 N
d) 1620 N
Kindly answer sir/mam.