 |
GNP501S - GENERAL PHYSICS - 1ST OPP - JUNE 2022 |
|
|
1 Page 1 |
▲back to top |
go
NAMIBIA UNIVERSITY
OF SCIENCE AND TECHNOLOGY
FACULTY OF HEALTH, APPLIED SCIENCES AND NATURAL RESOURCES
DEPARTMENT: NATURAL AND APPLIED SCIENCES
QUALIFICATION
QUALIFICATION
07BHOR
: BACHELOR OF SCIENCE
BACHELOR OF HORTICULTURE
CODE: 07BOSC,
LEVEL: 5
COURSE CODE: GNP501S
COURSE NAME: GENERAL PHYSICS 1A
SESSION: JUNE 2022
DURATION: 3 HOURS
PAPER: THEORY
MARKS: 100
FIRST OPPORTUNITY EXAMINATION QUESTION PAPER
EXAMINER(S) | DR MUNYARADZI ZIVUKU
MODERATOR: | PROF. DIPTI SAHU
Instructions
Answer all questions.
Answer the questions in the booklet provided
All written work MUST be done in blue or black ink
Mark all answers clearly with their respective question numbers
THIS EXAMINATION PAPER CONSISTS OF 5 PAGES (INCLUDING THIS FRONT PAGE)
|
|
2 Page 2 |
▲back to top |
SECTION A
QUESTION 1
1.1. Power is measured in:
A. Ws
B. Js"
C. m/s
(20)
(2)
D. W2
1.2 Oneof these statements is not true for acceleration due to gravity, g.
(2)
A. itis not a constant
B. itis a universal constant
C. itis a vector quantity
D. its magnitude is bigger than 0.
1.3. Whenever a liquid is touched slightly, small ripples run across the surface.
This statement is an evidence of ............ beseeseeee
(2)
A. surface tension
B. capillarity
C. angle of contact D. proxy
1.4 A streamline flow is also called ............
(2)
A. Laminar flow
B. Turbulent flow
C. Volume flow
D. Bernoulli's flow
1.5 A steel bar is precisely 1.60 m at 25° C. Its length is then increased to 1.64 m?
Determine its initial temperature in Kelvin.
(2)
A. 273
B. 198
C. 25
D. 298
1.6 How much heat is required to raise the temperature of a 0.04 kg stainless
steel cup from 20°C to 50°C if the specific heat capacity of stainless
steel is 0.50 kJ / kg.°C.
(2)
A. 200 J
B. 400 J
C. 800 J
D. 1000 J
1.7
ee is a vector that is tangential to path of an object in a circle:
(2)
A. angular force
B. centripetal acceleration
C. centripetal velocity
D. centripetal force
1.8 beeee aes is a method of determining universal gravitational constant, G:
(2)
A. Simple pendulum method
B. Boyle’s method
C. Universal method.
D. Gravitational method
|
|
3 Page 3 |
▲back to top |
1.9 Determine the density of copper if a copper ball with radius 1 cm has
a mass of 37.3 g.
(2)
A. 7.77 x 10° kg.m-%
B. 44x 10*g
C. 8.88 x 10° kg.m-3
D. 1x10*g
1.10 Which statement is incorrect for assumptions made in the derivation of Bernoulli
equation?
(2)
A. The flow is steady
B. The flow is incompressible
C. The viscosity of fluid in non-zero
D. The flow is irrotational
SECTION B
QUESTION 2
(15)
2.1 Explain why or why not displacement, acceleration and velocity vector be added
together.
(4)
2.2 Determine whether the following equations are dimensionally correct, if NOT, how
can you make them dimensionally correct?
(i) P= VJogh
(3)
(ii) v =u +at?
(2)
2.3. In an investigation, small spheres are dropped into a long column of a viscous
liquid and their terminal speed V of a sphere depends on the product of powers
of its radius r, its weight mg and the viscosity n of the liquid. Derive an equation
for the velocity of the sphere using dimensional analysis.
(6)
QUESTION 3 (15)
3.1
Given three vectors;
a =j + 2j +3k,
b = 2] +3j + k
c = 7i +2j +k,
(i) Calculate (a +b).c
(3)
(ii) | Evaluate vector p, such that p = (a x b) + (ax c)
(5)
|
|
4 Page 4 |
▲back to top |
3.2 The distance covered by a car at a time, t is given by x = 20t + 6t*, calculate
(i) the instantaneous velocity when t = 1
(3)
(ii) the instantaneous acceleration when t = 1
(4)
QUESTION 4
(15)
4.1 Given that a car start with a speed of u km/h and attain a final velocity of v km/h
after a time t hours. Given that the distance covered by the car is H km, derive
an equation for the velocity of the car and also show that this velocity can be
written as:
v=vu* + 2aH
(5)
4.2 A projectile is launched from a cliff 100m above the ground with an initial
velocity of 200 m/sec at an angle of 30° above the horizontal ground.
Determine;
(ii) The maximum height reached by the projectile (H)
(5)
(ii) Time of flight ( T)
(5)
QUESTION 5
(10)
5.1. Differentiate between elastic and inelastic collision with reference to the
conservation of momentum and conservation of kinetic energy.
(2)
5.2 Show that the rate of energy transfer of a particle is given by;
fxv
(3)
5.3. A 1.0kg object moves to the right at 2.0 m/sec and collides with a stationary
3.0 kg object. Assume the two objects are not stuck to each other after
collision. Assuming elastic collision and both momentum and kinetic energy
are conserved, what will be the final velocities of the two objects.
(5)
|
|
5 Page 5 |
▲back to top |
QUESTION 6
(15)
6.1 A bicycle wheel starts from rest and accelerates to an angular frequency of
3.50 rev/s. Determine the wheel’s average period T and centripetal velocity Vc
of the edge of the a wheel when the radius is 0.75 m.
(5)
6.2 An object of mass mis attached to a spring of length /. If the spring is extended
by a distance e and released. Show that the period, T, of the oscillation is given
by T =2n EE
(4)
6.3. Aspacecraft of mass 256 kg land on the moon. Calculate the moon’s
gravitational acceleration, g, on the spacecraft. [Take mass of moon = 7.5 x
1022 kg, radius of the moon = 1.6 x 10 §m, G = 6.67 x 10-11 Nm 2 kg%]. Start
with two forces that can be used for this scenario.
(6)
QUESTION 7
|
(10)
7.1. Explain the terms adhesion and cohesion.
(3)
7.2 Describe two pieces of evidence for surface tension based on cohesive and
adhesive forces.
(4)
7.3 During the time when a man had flu, he ran a fever of 2.0°C above normal.
His body temperature was 39.0°C instead of the normal 37.0°C. Assuming
that the man has a mass of 80 kg and that the human body is mostly water,
how much heat is required to raise his temperature? [Take specific heat
capacity of liquid as, c = 4186 J/kg.°C]
(3)
END OF EXAMINATION QUESTION PAPER