Answer: option c.
Explanation: 3 identical resistors can only have 3 configurations
1) all 3 resistors in series
2) all 3 resistors in parallel
3) 2 parallel resistors in series with 1 resistor.
Case 1 : all 3 resistors in series
Let us assume each of the resistor has resistance value R.
The total resistor (Rt) of 3 resistors in series is given as
Rt = R1 + R2 + R3
Since R1=R2=R3=R
Rt = R+R+R = 3R.
Case 2: all 3 resistors in parallel.
The equivalent resistance of resistors in parallel is given by the formulae below.
1/Rt = 1/R1 + 1/R2 + 1/R3
Since R1=R2=R3=R
1/Rt = 1/R + 1/R + 1/R
1/Rt = 1 +1 +1/ R
1/Rt = 3/R
3 * Rt = R
Rt = R/3
Case 3: 2 parallel resistor in series with one
First is to get the equivalent resistance of the 2 parallel resistor.
1/Rt = 1/R1 + 1/R2
But R1=R2=R
1/Rt = 1/R + 1/R
1/Rt = 1 + 1/R
1/Rt = 2/R
2 *Rt = R
Rt =R/2.
R/2 in series with R has an equivalent resistance as shown below
Rt = R/2 + R
Rt = R + 2R/2
Rt = 3R/2
Since all the possible 3 configuration are listed above and there is no other then option c ( 2R/3) is not possible to achieve
Answer:
The correct answer is:
(a) 27.5 Joules
(b) 141.5 Joules
Explanation:
Given:
Energy,
Coefficient of performance refrigerator,
(a)
As we know,
⇒ 
or,
⇒ 
(b)
⇒ 
or,
⇒ 
-- The wavelength and the amplitude were described in my answer to your previous question.
-- A "compression" is a place where the wave is <em>compressed</em>. It's the darker section of the wave in the picture, where the wavelength is temporarily shorter, so several waves are all bunched up (compressed) in a small time.
-- A "rarefaction" is exactly the opposite of a "compression". It's a place where the wave gets more "<em>rare</em>" ... the wavelength temporarily gets longer, so that several waves get stretched out, and there are fewer of them in some period of time. The arrow in the picture points to a rarefaction.
Answer:
A) Force = 2303.925 N in the negative x-direction
B) F ≈ 143998.28 N
C) Ratio = 62.5
Explanation:
A) Since the brakes are the only thing making the van to come to a stop, then first of all, we will calculate the force (in a component along the direction of motion of the car) that the brakes will apply on the van.
Let's find the deceleration using Newton's law of motion formula;
v² = u² + 2as
where;
v = final velocity,
u = initial velocity,
s = displacement
a = acceleration
We are given;
u = 87.5 km/h = 24.3056 m/s
s = 125 m
v = 0 m/s
Thus;
0 = (24.3056)² + 2a(125)
- (24.3056)²= 250a
a = - 24.3056²/250
a = - 2.363 m/s²
Now, force = mass × acceleration
We are given mass = 975 kg
Thus;
Force = 975 x (-2.363)
Force = 2303.925 N in the negative x-direction
B) formula for kinetic energy is
KE = ½mv²
KE = ½(975)(24.3056)²
= 287996.568288 J
Work done on impact = F x 2
Thus;
2F = 287996.568288
F = 287996.568288/2
F ≈ 143998.28 N
C) Ratio = Force on car/braking force = 143998.284/2303.925 = 62.5
Since both hv same mass and elsstic collision, so their velocity will exchange. Bob A will stop and bob B will move with speed of A just before the collision.
Speed will be = squreroot ( 2*g*L)
L is length of pendulum
