THE UNIVERSITY OF NEW SOUTH WALES
SCHOOL OF PHYSICS
PHYS1121 PHYSICS 1A
EXAMINATION 2003
MID-SESSION 2
Total number of questions = 6
Total number of marks = 60
Question 1 [8 marks] An object is launched horizontally from the top of an
inclined plane (Figure 1). The plane makes an angle of 40o with the horizontal. The
launch speed is 5 m/s. Calculate how far down the incline the object ‘lands’. Ignore
all forces except gravity.
Question 2 [9 marks] A small spherical bead with a mass of 100 g slides
along a frictionless, semicircular wire of radius of 10 cm. The wire is rotating about a
vertical axis at a rate of 2 revolutions per second (Figure 2).
(a) Draw a clear diagram showing all the forces acting on the bead.
(b) Calculate the value of the angle θ at which the bead will remain stationary
relative to the rotating wire.
Question 3 [10 marks] A 2 kg block resting on a frictionless, inclined plane is
released 4 m from a massless spring whose force constant is k = 100 N/m. The plane
makes an angle of 30o with the horizontal (Figure 3). Calculate the maximum
compression of the spring caused when the mass hits the spring. [Hint: don’t forget
the compression of the spring when calculating distance travelled.]
Question 4 [12 marks] A uniform, solid rod of mass M = 0.8 kg and length L =
1.2 m hangs vertically from a pivot at its top. The rod is struck by a particle of mass
0.3 kg initially moving horizontally. The particle makes a perfectly inelastic collision
