Basic Science Test 19

Result

Basic Science Test 19

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

A man holds a ball of (1/2) kg in his hand. He throws it vertically upward. During this process his hand moves up by 40 cm and the ball leaves his hand with an upward velocity of 4 m/s. The constant force with which the man pushes the ball is

A
2 N

B
10 N

C
15 N

D
7 N
Question 2
1 / -0

A square plate having mass m and side length 'a', its moment of inertia along the axis passing through its diagonal is-

A
$$\dfrac{ma^2}{6}$$

B
$$\dfrac{ma^2}{12}$$

C
$$\dfrac{5ma^2}{12}$$

D
$$\dfrac{ma^2}{2}$$
Question 3
1 / -0

A force of 100 N need to be applied parallel to a smooth! inclined plane just to hold a body on it. The angle inclination of the inclined plane is $$30^{0}$$. How much horizontal force need to be applied to do the same?

A
50 N

B
87 N

C
100 N

D
115 N

Solution

$$mg \sin 30 = 100$$
$$mg/2 = 100$$
$$mg = 200 \space N$$
$$ma \cos \theta = mg \sin \theta$$
$$ma \cos \theta = 100$$
$$ma \sqrt{3}/2 = 100$$
$$\Rightarrow ma = 200/\sqrt{3} \approx 115 \space N $$
Question 4
1 / -0

Moment of inertia of a thin circular plate of mass M, radius R about an axis passing through its diameter I. The moment of inertia of a circular ring of mass M, radius R about an axis perpendicular to its plane and passing through its centre is

A
$$2I$$

B
$$\dfrac{I}{2}$$

C
$$4I$$

D
$$\dfrac{I}{4}$$

Solution

We know a moment of inertia of a disc, axis passing through its diameter is $$I = \dfrac{MR^2}{4}$$
$$\therefore I' = MR^2$$
$$I'=4I$$
Question 5
1 / -0

A man and woman are both heterozygous for the recessive allele that causes cystic fibrosis. What is the probability that their first two off spring will have the disorder ?

A
$$1$$

B
$$1 / 4$$

C
$$1 / 16$$

D
$$1 / 32$$
Solution
Correct option: C

Explanation:
Cystic fibrosis is an autosomal recessive disorder, which means the cell should have both affected chromosome to become affected.
The Man and Female are both heterozygous with affected recessive allele i.e., $$X^CY$$ and $$X^CX$$ are crossed.
$$X^C$$ $$Y$$
$$X^C$$ $$X^CX^C$$ $$X^CY$$
$$X$$ $$X^CX$$ $$XY$$
Out of 4 only 1/4 is affected. Therefore, the probability of having the disorder in first two off spring would be 1/4 X 1/4 = 1/16.
Thus, Option C is correct.
Question 6
1 / -0

Let us consider a system of units in which mass and angular momentum are dimensionless. If the length has dimension of L, then the dimension of power is

A
$$L^{-2}$$

B
$$L^{-4}$$

C
$$L^{-6}$$

D
$$L^{3}$$

Solution

$$[M] = mass = M^0L^0T^0$$
$$J(R)$$ = angular momentum
$$e = mvR = \dfrac{mL^2}{T}$$
$$m \rightarrow$$ Dimensionless
$$T = L^{2}$$
L is also Dimensionless
Now $$P = mv = \dfrac{mL}{T}$$
m is dimensionless
$$[P] = L^{-1}$$
Power = $$\dfrac{mL^2}{T^2 . T} = \dfrac{L^2}{L^2T^2L} = L^{-4}$$
Question 7
1 / -0

A long capillary tube with both ends open is filled with water and set in a vertical position. The radius of the capillary is $$0.1\ cm$$ and surface tension of water is $$70$$ dynes/ cm. The length of the water column remaining in the capillary tube will be approximately.

A
$$1.5\ cm$$

B
$$2.9\ cm$$

C
$$3.6\ cm$$

D
$$5.8\ cm$$

Solution

Weight of fliuid = Surface tension force at both end
$$\pi r^2 d_0gh =2F=4\pi r\alpha$$

$$h=\dfrac {4\alpha}{d_0 gr}$$

here $$\alpha$$ is surface position

$$h=3\ cm$$

$$3.14\times (0.1)^2 \times 10^{-4}\times 100\times 10\times h$$

$$=4\times 3.14\times 0.1\times 10^{-2}x$$

$$h=\dfrac {4\times 70\times 10^{-5}/ 10^{-2}}{1000\times 10\times 0.1\times 10^{-2}}$$

$$=\dfrac {280\times 10^{-5}}{10^{-1}}$$

$$=280\times 10^{-4}m$$

$$=0.28\times 10^{-2}m$$

$$=0.28\ cm$$
Question 8
1 / -0

A torque of magnetude 200 Nm acting body produces an angular acceleration of 8 $$ rad / s ^{ 2} .$$ . The moment of inertia of the body is

A
$$ 25 kg - m ^{2} $$

B
$$ 12.5 kg - m ^{2}$$

C
$$ 50 kg - m ^{2}$$

D
$$ 75 kg - m ^{2} $$
Question 9
1 / -0

A torque of magnetude 200 Nm acting body produces an angular acceleration of 8 $$ rad / s ^{ 2} .$$ . The moment of inertia of the body is

A
$$ 25 kg - m ^{2} $$

B
$$ 12.5 kg - m ^{2}$$

C
$$ 50 kg - m ^{2}$$

D
$$ 75 kg - m ^{2} $$
Question 10
1 / -0

If $$Z= \frac{A}{A-B}$$ and $$A$$ and $$B$$ are measured with error $$\Delta A$$ and $$\Delta B$$ respectively, then relative error in $$Z$$, that is $$\frac{\Delta Z}{Z}$$ is equal to

A
$$\frac{\Delta A}{A} + \frac{\Delta A + \Delta B}{A- B}$$

B
$$\frac{\Delta A}{A} - \frac{\Delta A - \Delta B}{A- B}$$

C
$$\frac{\Delta A}{A} - \frac{\Delta A + \Delta B}{A- B}$$

D
$$\frac{\Delta A}{A} - \frac{\Delta A + \Delta B}{A+B}$$

Solution

$$Z= \dfrac{A}{A-B}$$

take log both sides

$$\log z= \log \left[ \dfrac{A}{A- B} \right]$$

$$\log z = \log A - \log (A - B)$$

differentiate -

$$\dfrac{\Delta Z}{Z}=\dfrac{\Delta A}{A} - \dfrac{\Delta A - \Delta B}{A- B}$$

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

	$$X^C$$	$$Y$$
$$X^C$$	$$X^CX^C$$	$$X^CY$$
$$X$$	$$X^CX$$	$$XY$$

Basic Science Test 19

Result

Basic Science Test 19

Score

-

Rank

-

SHARING IS CARING

Question 1

2 N

10 N

15 N

7 N

Question 2

$$\dfrac{ma^2}{6}$$

$$\dfrac{ma^2}{12}$$

$$\dfrac{5ma^2}{12}$$

$$\dfrac{ma^2}{2}$$

Question 3

50 N

87 N

100 N

115 N

Solution

Question 4

$$2I$$

$$\dfrac{I}{2}$$

$$4I$$

$$\dfrac{I}{4}$$

Solution

Question 5

$$1$$

$$1 / 4$$

$$1 / 16$$

$$1 / 32$$

Solution

Question 6

$$L^{-2}$$

$$L^{-4}$$

$$L^{-6}$$

$$L^{3}$$

Solution

Question 7

$$1.5\ cm$$

$$2.9\ cm$$

$$3.6\ cm$$

$$5.8\ cm$$

Solution

Question 8

$$ 25 kg - m ^{2} $$

$$ 12.5 kg - m ^{2}$$

$$ 50 kg - m ^{2}$$

$$ 75 kg - m ^{2} $$

Question 9

$$ 25 kg - m ^{2} $$

$$ 12.5 kg - m ^{2}$$

$$ 50 kg - m ^{2}$$

$$ 75 kg - m ^{2} $$

Question 10

$$\frac{\Delta A}{A} + \frac{\Delta A + \Delta B}{A- B}$$

$$\frac{\Delta A}{A} - \frac{\Delta A - \Delta B}{A- B}$$

$$\frac{\Delta A}{A} - \frac{\Delta A + \Delta B}{A- B}$$

$$\frac{\Delta A}{A} - \frac{\Delta A + \Delta B}{A+B}$$

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.