As physics p1 MCQS YEARLY ONLY.

[ALFRED DEI AMOEH]

I think I can help for 2007 May /June Q3 . the answer is (a) because (g) X (lamda) would have a unit of m squared and per second squared. the root of this unit gives a unit of meter per second.

 

[Thought blocker]

I think I can help for 2007 May /June Q3 . the answer is (a) because (g) X (lamda) would have a unit of m squared and per second squared. the root of this unit gives a unit of meter per second.

Whom are you answering ?

 

[dumb human]

November 2007

1-C
Use base units and equate both sides.

2-A
Learn the approximations.

3-B
Resultant force is always is opposite direction of its two components in the triangle of forces.

4-D
Precision is the closeness of measured values.
Accuracy is the closeness of measured values to actual value.

5-C
P = fv
f = ma and v = s/t

P = add up all the % uncertainties.
%P = 0.1 + 1 + 1.5 + .5
= 3.1 %

6-A
Due to zero error, the initial value of angle of deflection will be greater than zero at zero current.

7-A
Basic concept that g gravity is the acceleration of free fall.

8-D
The gradient of velocity-time graph is acceleration.


9-B

Area of distance above x axis - area of distance below x axis.
(0.5 * 3 * 30) - (.5 * 2 * 20)
= 25 m

10-D

Driving force - frictional force = ma
12- Fre = 0.6(4)
12- 0.6(4) = Fre
9.6 N = Fre

11- B
View attachment 12245

12-A
Since the parachutist is falling, height is decreasing over time.
Gradient of distance-time graph is speed.

13-C
Use head to tail method.

14-D
At midpoint, d = 0.8/2 = 0.4m
Moment = F*d
12 = F * 0.4
30 N = F

15-B
Initial K.E. - Final K.E.
(0.5* 1000 *25^2) - (0.5 * 1000 * 5^2)
300 000 J
300 kJ

16 - C
At max d, K.E. = minimum and elastic potential energy = maximum.

17-C
Density = mass/volume
Hence higher density means a higher mass, hence more no. of atoms.
So MpNp > MqNq

18-A
Height at surface =?
Pressure = density * g* h
100 000= 1030 * 9.81 * h
9.896 m = h1

Height at 450 kPa =?
450 000 = 1030 * 9.81 * h
44.535 = h2

Therefore height below surface = 44.535 - 9.896
=34.639 ~ 34.6m

19-B
Basic definition.

20- A
Strain energy = 1/2 * F * extension
= 0.5 * 25 * (0.4 - 0.2)
= 2.5 J

21- B
View attachment 12247

22- B
Learn the wavelengths.

23- B
Max speed = 2pii *a *f
f = ?
s = f* lamda
8 = f (50)
0.16 Hz = f

Max speed = 2pii * 2 * 0.16
=2 m/s
Max K.E. = .5 m* v^2 = 0.5 * 2 * 10^-3 * 2^2
= 4 mJ

24-D
x = lamda * D/ a

Hence increasing the lamda, increases x, that is the fringe separation.

25-B

d sin theta = n* lamda
At n = 3, theta = 45 degrees
d sin45 = 3*lamdaa
0.7 d = 3 lamda

and max angle = 90 , so n =?
d sin90 = n*lamdaa
d = n* lamda

Using the ratio method:
If 0.7d = 3 lamda
1 d =?
cross multiply and you get n as 4.25 hence rounding it off to 4th order.

26- C
Since electric field direction is from higher p.d./charge to lower p.d./charge the electron will be attracted towards the more positively charged plate (or direction) hence to the left.

27-D
Direction of electric field is away from positive charge.

28-B
E = V*Q
E/Q = V

29-D

P = V^2/R
P = 12^2/Rx and P = 6^2/Ry
Rx = 144/P and Ry = 36/P

Rx/Ry = 144/P divided by 36/P
Rx/Ry = 144/36 = 4

30-D

V = IR
6 = I (10 +10)
0.3 A = I

Q = It
0.3 * 60 = 18 C

31-A

View attachment 12248

32-A

Basic concept of L.D.R.; when light intensity increases, resistance decreases hence voltage decreases too.

33-D
V in = R1/T.R. * V out
4.8 = 10/25 * V out
4.8* 25/10 = V out
12 = V out

34-D
Using the ratio method:
If 1.1 V - 0.7 m
? - 0.9 m
x = 0.9* 1.1/ .7
x = 1.4 V

35-A
The readings won't change because the set up is the same.

36- C
Charge is same since proton no. is same, but mass differs since no. of neutrons differs.

37- C
Basic concept.

38-C
The alpha scattering experiment proves the small size of a gold nucleus.

39-B
In a beta emission, the nucleon no. remains same but the proton no. increases by 1
For 2 beta emissions, proton no will increase by 2 hence 40 +2 = 42

40-A
Momentum = mv, greater m = greater momentum.
hence the particle with the greatest mass from all the choices is A, an alpha particle.

Can you please explain 33) IN DETAIL =(

 

[Thought blocker]

Can you please explain 33) IN DETAIL =(

Hello Ma'am. Good morning.
Here is your explanation:¬
We are asked to find out Vout we are provided with Vin as 4.8V total resistance of circuit as 25kΩ
So here is the formula : Vin = R1 / Total resistance * Vout
Equate values:
4.8 = 10000 / 25000 * Vout
Vout = 4.8 * 2.5 = 12V = D

 

[dumb human]

Hello Ma'am. Good morning.
Here is your explanation:¬
We are asked to find out Vout we are provided with Vin as 4.8V total resistance of circuit as 25kΩ
So here is the formula : Vin = R1 / Total resistance * Vout
Equate values:
4.8 = 10000 / 25000 * Vout
Vout = 4.8 * 2.5 = 12V = D

Thank you sooooo much sir!!!!!
Now i got it =D
it's night by the way =P

 

[Thought blocker]

Thank you sooooo much sir!!!!!
Now i got it =D
it's night by the way =P

2:40 AM is morning ma'am.
Can you prove K.E as 0.5*m*v^2 ?

 

[Thought blocker]

Thank you sooooo much sir!!!!!
Now i got it =D
it's night by the way =P

Well what were you facing problem at ?

 

[Farhana.sultana]

21)
We just take ρ = m / v formula in account to solve this question (where ρ is density, m is mass and v is volume)

We are asked to find total density
to calculate total density, we need total mass and total volume
from question we can see that it is given the two masses are equal that means total mass is just sum of m + m = 2m

Now lets look towards total volume so:¬
Masses are equal so I would make two conditions, so that it would be easier to understand (for (i) I would use m and for (ii) I would use m) KEEP Remember masses are equal
i) m is given and we are give it has density ρ so volume of 1st mass = m / ρ
ii) m is given and also given density of 2ρ so volume of second mass = m / 2ρ
add (i) and (ii) it will give us a total volume of 3m / 2ρ

Now, final part:¬
For total total density (td), td = total mass / total volume

=>td = (2m*2ρ) / 3m
=> td = 4mρ / 3m (cut m)​

=> td = 4ρ/3 = A option

Thnx a lot nw I got

 

[dumb human]

Well what were you facing problem at ?

i was confused....its like they mostly ask as to find Vout.....but here it was opposite...so i was like haiiiiiiiiiiin yeh kya? xD

 

[Thought blocker]

Thnx a lot nw I got

Not a problem, well where were you perplexed ?

i was confused....its like they mostly ask as to find Vout.....but here it was opposite...so i was like haiiiiiiiiiiin yeh kya? xD

LOL Ma'am, basic math hai vo to

 

[dumb human]

Not a problem, well where were you perplexed ?

LOL Ma'am, basic math hai vo to

meine maths naii laytii na =P

 

[Thought blocker]

meine maths naii laytii na =P

Ji bachpan se apney math lia hi nahi kiya ?

 

[dumb human]

Ji bachpan se apney math lia hi nahi kiya ?

hahahahah 10 tak xD

 

[Thought blocker]

hahahahah 10 tak xD

To bhi basic ni ati ?

 

[dumb human]

To bhi basic ni ati ?

C grade aya tha =P
Soochlo mayri basics kaisi hosakti hayn xD

 

[Thought blocker]

C grade aya tha =P
Soochlo mayri basics kaisi hosakti hayn xD

Lets make a convo

 

[dumb human]

Lets make a convo

Woh toe ban he gaey =P

 

[Thought blocker]

Woh toe ban he gaey =P

Y should we talk here n give others alerts ?

 

[Farhana.sultana]

Lol wht u guys r doing?

 

[Thought blocker]

Lol wht u guys r doing?

Nothing, tp