Download Midterm Examination

THE INTERNATIONAL UNIVERSITY (IU)
VIETNAM NATIONAL UNIVERSITY - HCMC
ASSIGNMENT
SUBJECT: PHYSICS
1
GROUP: 7 – 10 STUDENTS
(To submit the 08th AUGUST 2016)
Student Name:_______________________Student ID:___________________
1/ (20 pts) A 3-kg particle starts from rest at x = 0 and moves under the influence of a single force
F = 6 + 4x - 3x2, where F is in newtons and x is in meters.
(a) Find the work done by the force as the particle moves from x = 0 to x = 3 m.
(b) Find the power delivered to the particle when it is at x = 3 m.
2/ (20 pts) A 2-kg box is projected with an initial speed of 3 m/s up a rough plane inclined at 60 o above
horizontal. The coefficient of kinetic friction is 0.3.
(a) What is the energy dissipated by friction as the box slides up the plane?
(b) What is the speed of the box when it again reaches its initial position?
3/ (20 pts) A spring of negligible mass has force constant k = 1600 N/m.
(a) How far must the spring be compressed for 3.20 J of potential energy to be stored in it?
(b) You place the spring vertically with one end on the floor. You then drop a 1.20-kg book onto it from a
height of 0.80 m above the top of the spring. Find the maximum distance the spring will be compressed.
4/ (20 pts) A particle of mass 5 kg, moving at 2 m/s, collides with a particle of mass 8 kg initially at rest. If
the collision is elastic, find the velocity of each particle after the collision
(a) if the collision is head-on.
(b) if the first particle is defected 50o from its original direction of motion. Express all directions relative to
the direction of the incoming particle.
5/ (20 pts) Block A in Fig. 1 has mass 1.00 kg, and block B has mass
3.00 kg. The blocks are forced together, compressing a spring between
them; then the system is released from rest on a level, frictionless
surface. The spring, which has negligible mass, is not fastened to either
block and drops to the surface after it has expanded. Block B acquires a
speed of 1.20 m/s.
(a) What is the final speed of block A?
(b) How much potential energy was scored in the compressed spring?
THE END
A
B
Fig.1