0.94s
0.96s
0.93s
0.95s
Correct answer is B
d=312m.,T =263\(-10^°c\) = -10+273K = 263K, t=?
v= 331√ \(\frac{T}{273}\)
⇒ v = 331×√ \(\frac{263}{273}\)
⇒ v = 324.88 \(ms^-1\)
⇒ v = \(\frac{d}{t}\)
t = \(\frac{d}{t}\) = \(\frac {312}{324.88}\)
t = 0.96s
X = α-particle; Y = γ-ray; Z = β-particle
X = α-particle; Y = β-particle; Z = γ-ray
X = γ-ray; Y = α-particle; Z = β-particle
X = β-particle; Y = γ-ray; Z = α-particle
Correct answer is C
The penetrating power of alpha rays, beta rays, and gamma rays varies greatly. Alpha particles can be blocked by a few pieces of paper. Beta particles pass through paper but are stopped by aluminum foil. Gamma rays are the most difficult to stop and require concrete, lead, or other heavy shielding to block them.
Therefore, X = γ-ray; Y = α-particle; Z = β-particle
The sensitivity of a thermometer is
All of the above
how quickly a temperature change can be detected
the difference between the maximum and the minimum temperature
the smallest temperature change that can be detected or measured
Correct answer is D
The sensitivity of a thermometer is defined as the smallest temperature change that can be detected or measured, NOT how quickly that temperature change can be detected.
In contrast, the difference between the maximum and the minimum temperature is the range of a thermometer
108,986 Pa
165,238 Pa
122,364 Pa
134,645 Pa
Correct answer is D
density (ρ) = 13600 \(kgm^{-3}\); g =\(9.8 ms^{-2}\)
\(P_{atm}\) =101,325 Pa; ρ=13600 \(kgm^{-3}\)
Pabs=\(P_{atm}\)+ρgh
⇒Pabs=101,325+13600 x 9.8 x 0.25
⇒Pabs=101,325+33320
⇒ Pabs=134,645Pa
\(29.36^o\)
\(25.37^o\)
\(37.21^o\)
\(34.75^o\)
Correct answer is D
\(n_1\)=1.33; \(n_2\)=1.5; i=40°; r= ?
from snell's law:
\(n_1\) x sin i=\(n_2\)x sin r
⇒1.33 x sin 40°=1.5 x sin r
⇒sin r = 0.5700
⇒r = \(sin^{-1}\) (0.5700)
⇒ r = 34.75
7.2 kJ
4.6 kJ
6.8 kJ
8.4 kJ
Correct answer is A
The work done against the gravitational force is calculated using the formula W = mgh, where m is the mass of the object, g is the acceleration due to gravity (approximately \(9.8 ms^2\) on Earth), and h is the height. Substituting the given values, we get W = 3.0 kg * \(9.8 m/s^2\) * 240 m = 7.2 kJ. Therefore, the correct answer is '7.2 kJ'.
47 g
52.8 g
37.6 g
56.6 g
Correct answer is D
Let mb=mass of empty bottle,
\(m_w\)=mass of water only and
\(m_a\)= mass of alcohol only
given; \(m_b\)=19g
\(m_b\) + \(m_w\) = 66g
\(m_b\) + \(m_a\) = ?
R.d=0.8
R.d=mass of alcohol
⇒\(\frac{mass of alcohol}{mass of equal volume of water}\)
⇒ mass of equal volume of water = \(m_w\)=66-19=47g
⇒0.8 = \(\frac{m_a}{47}\)
⇒\(m_a\)=0.8×47 =37.6g
; \(m_b\) + \(m_a\) = 19+37.6=56.6g
26.25 cm behind the mirror
10.5 cm behind the mirror
26.25 cm in front of the mirror
10.5 cm in front of the mirror
Correct answer is B
f= -15cm (diverging mirror); u=35cm; v=?
⇒\(\frac{1}{f}\) = \(\frac{1}{u}\) + \(\frac{1}{v}\)
⇒ \(\frac{1}{-15}\) = \(\frac{1}{35}\) + \(\frac{1}{v}\)
⇒ \(\frac{1}{15}\) - \(\frac{1}{35}\) = \(\frac{1}{v}\)
⇒ \(\frac{-2}{21}\) = \(\frac{1}{v}\)
= \(\frac{-21}{2}\) = -10.5cm
∴The image is 10.5cm behind the mirror
800 Hz
600 Hz
400 Hz
200 Hz
Correct answer is A
T=800N; I=50cm=0.5m,
m=10g=0.01kg
fundamental freq: \(f_o\) =?
\(f_o\) = \(\frac{1}{21}√{T}{μ}\)
μ =\(\frac{m}{1}\)=\(\frac{0.01}{0.5}\)
⇒ \(f_o\) =\(\frac{1}{2×0.5}\)√\(\frac{800}{0.02}\)
\(f_o\) ⇒√ 40,000
⇒1st overtone = 2\(f_o\) =2×200 = 400Hz
⇒2nd overtone =3\(f_o\) =3×200=600Hz
∴3rd over tone= 4\(f_o\) =4×200=800Hz
40 kΩ
37.5 kΩ
45.5 kΩ
30 kΩ
Correct answer is B
For the combination in series;
⇒R1 = 35kΩ + 40kΩ = 75kΩ
R is combined with 75kΩ in parallel to give 25kΩ
= \(\frac{1}{R_eq}\) = \(\frac{1}{R}\) + \(\frac{1}{R}\)
= \(\frac{1}{25}\) = \(\frac{1}{R}\) + \(\frac{1}{75}\)
= \(\frac{1}{25}\) - \(\frac{1}{75}\) + \(\frac{1}{R}\)
= \(\frac{3-1}{75}\) = \(\frac{1}{R}\)
= \(\frac{2}{75}\) = \(\frac{1}{R}\)
= \(\frac{75}{2}\) = R
; R = 37.5k Ω
Information and Communication Manager at Nigerian Breweries Plc
Area Sales Manager at Airtel Nigeria
State Business Manager at Airtel Nigeria
Regional Technical Officer at Airtel Nigeria
Business Manager at Airtel Nigeria
Contract Administrator at Robert Walters
Import & Export Manager at Kerildbert Holdings Limited
JV Account Payable Officer at WTS Energy
HR Intern, Learning and Development at MainOne Cable
Senior Technical Officer - Endemic Diseases & NTDs (AfCDC) at the African Union