The diagram above shows a velocity time graph representing the motion of a car. Find the total distance covered during the acceleration and retardation of the motion
A75m
B150m
C300m
D375m
View Explanation & Discuss
Question 872
jamb1993
The kinetic theory of photoelectron liberated from a metallic surface depends on the
Aintensity of the incident radiation
Btime duration of the incident radiation
Ctemperature of the incident radiation
Dfrequency of the incident radiation
View Explanation & Discuss
Question 873
jamb1993
An element X of an atomic number 88 and mass number 226 decays to form an element Z by emitting two beta particles and an alpha particle. Z is represented by
A\(^{222}_{82}Z\)
B\(^{222}_{88}Z\)
C\(^{226}_{86}Z\)
D\(^{226}_{80}Z\)
View Explanation & Discuss
Question 874
jamb1993
Which of the following are produced after a nuclear fusion process? i. one heavy nucleus. ii. neutrons-1. iii. protons. iv. Energy.
Ai and ii
Bi and iv
Cii and iii
Dii and iv
View Explanation & Discuss
Question 875
jamb1993
Natural radioactivity is the random spontaneous disintegration of the nuclei of heavy isotopes of certain elements with the emission of
A\(\alpha\), X, and \( \beta\)
B\(\alpha\), \(\beta\) and \(\gamma\)-rays
CX, \(\alpha\), \(\gamma\)-ray
D\(\alpha\), \( \beta\) and X-rays
View Explanation & Discuss
Question 876
jamb1993
Which of the following statements correctly describe(s) cathode rays? i. they consist of tiny particles carrying negative electric charges. ii. they are deflected in a magnetic field but not in an electric field. iii. they consist of fast moving neutrons and deflected in an electric field.
Ai only
Bii only
Ci and ii only
Dii and iii only
View Explanation & Discuss
Question 877
jamb1993
Determine the inductive reactance when a 30.0mH inductor with a negligible resistance is connected to a 1.3 x 103Hz oscillator.
A39.0\(\Omega\)
B122.5\(\Omega\)
C245.0\(\Omega\)
D39000.0\(\Omega\)
View Explanation & Discuss
Question 878
jamb1993
The primary aim in high tension transmission is to
Aminimize electrical energy losses due to heat production
Bincrease the rate of energy transfer by using high voltage
Cincrease the current in the wire
Dgenerate electricity at high current and low voltage
View Explanation & Discuss
Question 879
jamb1993
Which of the following devices may be used to step up the voltage in a d.c. circuit?
Aa step-up transformer
Ba d.c. generator
Ca wattmeter
Dan induction coil
View Explanation & Discuss
Question 880
jamb1993
A 40-W instrument has a resistance of 90\(\Omega\). On what voltage should it be operated normally?
A60V
B150V
C225V
D3600V
View Explanation & Discuss
Question 881
jamb1993
A parallel plate capacitor of area 10cm2 in vacuum has a capacitance of 10-2\(\mu\)F. What is the distance between the plates?(e = 9 x 10-12fm)
A9 x 10-13m
B9 x 10-7m
C9 x 10-3m
D9 x 107m
View Explanation & Discuss
Question 882
jamb1993
A current of 100mA passes through a conductor for 2 minutes. The quantity of electricity transported is
A200C
B50C
C12C
D0.002C
View Explanation & Discuss
Question 883
jamb1993
The terminal voltage of a battery is 4.0V when supplying a current of 2.0A, and 2.0V when supplying a current of 3.0A. The internal resistance of the battery is
A0.5 \(\Omega\)
B1.0\(\Omega\)
C2.0\(\Omega\)
D4.0\(\Omega\)
View Explanation & Discuss
Question 884
jamb1993
A simple cell with mercury-amalgamated zinc electrode prevents
Alocal actions
Bpolarization
Cbuckling
Ddegradation
View Explanation & Discuss
Question 885
jamb1993
A current carrying conductor experiences a force when placed in a magnetic field because the
Aconductor is magnetized
Bmagnetic field of the current interacts with external magnetic field
Cforce is due to the motor principle
Delectric field of the current interacts with the external magnetic field
View Explanation & Discuss
Question 886
jamb1993
Which of the following correctly explains why soft iron is proffered to steel in electromagnets? i. soft iron is more readily magnetized than steel. ii. soft iron is more readily demagnetized than steel. iii. soft iron retains magnetism more than steel.
Ai only
Bii and iii only
Ci and ii only
Di, ii, and iii.
View Explanation & Discuss
Question 887
jamb1993
Which of the following correctly explain(s) why a green leaf appears green in bright day light? i. it absorbs only the green component of sunlight. ii. it absorbs all colour of sunlight except green. iii. it reflects only the green component of sunlight.
Ai only
Bii only
Ci and iii only
Dii and iii only
View Explanation & Discuss
Question 888
jamb1993
The property of the eye known as its power of accommodation is controlled by the
Apupil
Bvirteous humour
Ciris
Dciliary muscles
View Explanation & Discuss
Question 889
jamb1993
A beam of light is incident from air to water at an angle of 30oC. Find the angle of refraction if the refractive index of water is \(\frac{4}{3}\)
A15oC
B18oC
C22oC
D24oC
View Explanation & Discuss
Question 890
jamb1993
Which of the following may be used to explain a mirage? i. layers of air near the road surface have varying refractive indices in hot weather. ii. road surfaces sometimes become good reflectors in hot weathers. iii. light from the sky can be reflected upwards after coming close to the road surface.
