1990 - JAMB Physics Past Questions and Answers - page 5
41
A substance has a half of 3mins. after 6mins. the count rate was observed to be 400. What was its count rate at zero time?
A
200
B
1200
C
1600
D
2400
correct option: c
Users' Answers & Comments42
The photocell works on the principle of the
A
voltaic cell
B
emision of electrons by incident radiation
C
emision of protons by incident electrons
D
photographic plate
correct option: b
Users' Answers & Comments43
![](https://publicappmediaqa.s3.eu-central-1.amazonaws.com/21560_1.jpg)
A
1.88cm
B
1.80cm
C
1.28cm
D
1.97cm
correct option: a
Users' Answers & Comments44
![](https://publicappmediaqa.s3.eu-central-1.amazonaws.com/21561_1.jpg)
A
2√3/3N
B
√2N
C
4√3/3
D
2V3N
correct option: d
Users' Answers & Comments45
![](https://publicappmediaqa.s3.eu-central-1.amazonaws.com/21562_1.jpg)
A
85.0ms-1
B
17.0ms-1
C
8.5ms-1
D
1.7ms-1
correct option: c
Users' Answers & Comments46
![](https://publicappmediaqa.s3.eu-central-1.amazonaws.com/21563_1.jpg)
A
0Nm
B
3Nm
C
7Nm
D
10Nm
correct option: a
Users' Answers & Comments