Physics: Post your doubts here!

[GarryTheGhost]

A giant squid of length 20.0m is vertical in seawater, with the top of the squid at a depth of
8.00m. The density of seawater is 1050kgm–3.
What is the difference in pressure between the top and the bottom of the squid?
A 82000Pa B 206000Pa C 288000Pa D 389000Pa
Anyone?

use the pressure formula= density*g*depth
use depth as 20m

 

[GarryTheGhost]

how do we do this????

 

[dumbledore.]

Q19.
Ans=C

 

[GarryTheGhost]

how do we do this????

nvm i got it

 

[selrey]

use the pressure formula= density*g*depth
use depth as 20m

Ohh thankyou!

 

[GarryTheGhost]

Q19.
Ans=C

first find the power produced by the engine itself. so using force*velocity=power hence 30000/25=1200N
notice the car maintains 25m/s therefore forces are balanced and there is no net force.
we need to calculate the weight down the slope.
so 1400*g*sin(2)=479.3.....N
the car has to overcome this force to maintain a constant velocity and it does this by producing an extra output power of 479.3....N*25=12000watts
so total output power= 12000+30000=42000

 

[Minsa Fatima]

can anyone please explain this?

 

[GarryTheGhost]

can anyone please explain this?View attachment 62515

ans????

 

[Minsa Fatima]

ans????

B

 

[Minsa Fatima]

And this one too..

 

[GarryTheGhost]

can anyone please explain this?View attachment 62515

we first need to find the voltage in the external resistance. so using v=ir
hence v=5.5v. since the all of the components are parallel to each other they all have an terminal potential difference of 5.5v
current going into the junction= output of junction.
so the current going into the internal resistance is 0.25A. 0.5/2 as both components have the same p.d and internal resistance they both have the same current
simply then use the formual
terminal p.d=Emf-Ir
5.5=6-0.25r
hence r is 2 ohms

 

[Minsa Fatima]

no ans is B

 

[Minsa Fatima]

we first need to find the voltage in the external resistance. so using v=ir
hence v=5.5v. since the all of the components are parallel to each other they all have an terminal potential difference of 5.5v
current going into the junction= output of junction.
so the current going into the internal resistance is 0.25A. 0.5/2 as both components have the same p.d and internal resistance they both have the same current
simply then use the formual
terminal p.d=Emf-Ir
5.5=6-0.25r
hence r is 2 ohms

Thanks

 

[Shimmery woods]

And this one too..View attachment 62516

when two objects collide elastically then relatice speed of approach = relative speed of seperation
• Same direction = subtract speed
•Opposite direction= add speed
answer=A

 

[Minsa Fatima]

when two objects collide elastically then relatice speed of approach = relative speed of seperation
• Same direction = subtract speed
•Opposite direction= add speed
answer=A

thankyou

 

[GarryTheGhost]

And this one too..View attachment 62516

when two objects collide elastically then relatice speed of approach = relative speed of seperation
• Same direction = subtract speed
•Opposite direction= add speed
answer=A

lol beat me to it

 

[furuta]

Help with questions 15 and 29 please <3
http://papers.gceguide.com/A Levels/Physics (9702)/9702_m16_qp_12.pdf

 

[Minsa Fatima]

 

[Minsa Fatima]

Help with questions 15 and 29 please <3
http://papers.gceguide.com/A Levels/Physics (9702)/9702_m16_qp_12.pdf

15. mass=weight/gravity
600000/9.81=61162
KE=1/2 *61162*40*40
KE=12MV
Answer=C

29. W=QV
Fd=QV
F=1.6*10-19 *200/0.005
=6.4*10-15

 

[student4563543]

View attachment 62517

is B the answer?