PHYSICS

Question 1

5-10 MHz

Answer 1

to monitor blood flow through major arteries through ultrasonic waves

Question 2

Thermodynamics V=constant

Answer 2

workdone=zero

W=P∆V

Question 3

max height

Answer 3

H=gT2/8 obligue

Question 4

K.E and P.E projectile motion

Answer 4

K.E→K.Ecos2⊖

P.E→P.Esin2⊖

Question 5

direction of impulse and momentum

Answer 5

same at 0°

don’t look at v

Question 6

v=√2gh

Answer 6

∆h=h1-h2

Question 7

a boy swing in a sitting position if he stands up the period of the swing will be

Answer 7

as boy stands its center of gravity shifts upward and the length (from the the point where string is attached to the center of gravity of body) decrease
↓T∝√L↓
time period will be shorter

Question 8

the ratio of K.E at mean to P.E when displacement is half of amplitude

Answer 8

K.E=1/2k(x◦2-x2)
K.Emax=1/2kx◦2
P.E=1/2kx2
     =1/2kx◦2/2
4:1

Question 9

a bomb of mass 30kg is at rest explodes into pieces of mass 18kg and 12k. The velocity of 18kg mass is 6ms-1. The K.E of the other mass

Answer 9

Pi=Pf
0=m1v1+m2v2
v2=-9ms-1
K.E=1/2mv2
      =486J

Question 10

momentum and stopping potential

Answer 10

P=mv
P=mS/t
P∝S

Question 11

coefficient of a perfectly elastic collision

Answer 11

e = 1

Question 12

coefficient of a inelastic collision

Answer 12

e = 0

Question 13

The sphere have a head-on collision

Answer 13

X stick together
V total K.E after mv2
     =I/2mv2+1/2m(-v)2
     =mv2
V total momentum after collision
     =2mv

Question 14

/2=1.4
/3=1.7
/5=2.2

Question 15

Value of Coulombs constsnt is _______than gravitational constant.

Answer 15

Greater
9x109Nm2C-2
6.67 × 10-11Nm2kg-2

Question 16

A resister connected to a battery is heated T increase due to current through it

Answer 16

Only no. of free e’s same
R increase or decrease T increase
Even resistivity

Question 17

Photoelectric effect

Answer 17

Law of conservation of energy

Light energy Electrical energy convert

Question 18

P=Ft

Question 19

P=Ft

Question 20

Charging curve rise btw q and t

Dischaging/decay curve fall C

Question 21

Frequency of DC is 0

Frequency of AC is 50 Hz

Question 22

E=oT4
T=3T
E=81E

Question 23

Magnetic field cross
Current wire produce
Upward movent between magnets

Question 24

Magnitude of coulomb force ratio= 1:1

Forces ratio= 1:-1

Question 25

Useful tracer

Answer 25

Carbon 14

Question 26

Germanium=0.3

Silicon=0.7

Question 27

F=0

Answer 27

B=0
Angle 0° 180°
Velocity and B same direction

Question 28

Equal fraction disintegrates in equal interval of time

The rate of disintegration is directly proportional to the no of atoms present at that instant

Question 29

Equipotential surface

Answer 29

V constant
DelV =0
W =0

Question 30

Line of force in electric field

Answer 30

Farady

Question 31

n = p + e + antineutrino r-

Question 32

1 KWh=1 unit

Answer 32

Lamda s - lamda i

Question 33

E = N delO / delt
IR = delO / delt
I delt = delO / R
Q = delO / R

Question 34

Rod connected between two spheres
O(charge density)a = Ob
qa / Aa = qb / Ab
qa / pie ra2 = qb / pie rb2
 qa /qb = ra2 / rb2

Answer 34

Va = Vb

qa / qb = ra / rb

Question 35

V=kZqe/r

Answer 35

P=/2mK.E

Question 36

Projectile motion

Answer 36

T=2Visino/g
H=Vi2sin2o/2g
R=Vi2sin2o/g

Question 37

Rtano=4H

Answer 37

Workdone=0

Holding mass

Question 38

Alpha particles high ionizing

High charge and low speed

Answer 38

Street step down 1100V-220V

Question 39

What does change when constant force is kept applied on a body
Position

Answer 39

Isotopes in Xe and Cs

36

Question 40

O=2pielamda/x

Question 41

A 1000-kg airplane moves in straight flight at constant speed. The force of air friction is 1800 N. What is the net force on the plane?

Answer 41

Zero
The airplane is producing a constant force of 1800N and that’s the reason why the plane is moving with constant speed.

The net force is 1800 - 1800 = 0.

Question 42

V

Answer 42

electric potential V=kq/r
absolute potential V=W/q
potential difference or voltage V=IR=Ed

Question 43

rms

Answer 43

always positive
aka effective values
related to amplitude of the instantaneous sinusoidal values

Question 44

I◦ = /2 Irms

Question 45

the energy stored in electromagnetic or electrostatic field is called

Answer 45

electric potential energy