Join our jamb group on WhatsApp using the link below 👇
6.
The linear expansivity of brass is 2 x 10-5C-1. If the volume of a piece of brass is 15.00cm3 at 00C, What is the volume at 100oC?
A.
16.03cm3
B.
16.00cm3
C.
15.09cm3
D.
15cm3
correct option: C
explanation:
linear expansivity = \(\frac {V_2 - V_1}{V_1 {\times} {\Delta}{\theta}}\)
3 x 2 x 10-5 =\(\frac {V_2 - 15}{15 {\times} (100 - 0)}\)
V2 = 15.09cm3
7.
The lower and upper fixed points marked on a mecury-in-glass thermometer are 210mm apart. The end of the mercury column in the tube is 49mm above the lower fixed point in a room. What is the temperature of the room in degrees Celsius?
A.
55.3oC
B.
23.3oC
C.
49.0oC
D.
16.1oC
E.
3߀76.7oC
correct option: D
explanation:
210mm .... 100oC
49mm .... θ
0mm .... 0oC
49−0210−0 = θ−0100−0
49210 = θ100
θ = 23.3oC
8.
A few grains of table salt were put in a cup of cold water, kept at constant temperature and left undistributed. Eventually all the water tested salty. This action is due to?
A
convection
B
osmosis
C
capillarity
D
diffusion
correct option: C
explanation:
Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity.
9.
A machine gun with a mass of 5kg fires a 50g bullet at a speed of 100 ms. The recoil speed of the machine gun is
A
0.5 ms
B
1.5 ms
C
1 ms
D
2ms
correct option: C
explanation:
Gun momentum = bullet momentum
MV = MV
5 x V = 0.05 x 100
V = 1m
10. In what range of temperature is the expansion of water anomalous?
A
+208C to +212C
B
-80C + -76C
C
0C to +4C
D
-4C to +0C
correct option: C
explanation:
The anomalous expansion of water is an abnormal property of water whereby it expands instead of contracting when the temperature goes from 0C to +4C, and it becomes less dense
Posts
0 Comments