What is the pH of a neutral substance?

A gas has an initial volume of 168 cm3 at a temperature of 255 K and a pressure of 1.6 atm. The pressure of the gas decreases to

grandymaker [24]

P1V1/T1 = P2V2/T2

(1.6atm)(168cm^3)/(255K) = (1.3atm)V2/(285K)

Final volume = 231cm^3

6 0

4 years ago

Set up a parallel circuit with three resistors. Set up the battery to be 9 V, one resistor at 10 Ohms, the other at 21 Ohms, and

valina [46]

In a parallel circuit, the equivalent resistance is the reciprocal of (the sum of the individual reciprocals).

1/R = 1/10 + 1/21 + 1/13

1/R = 0.225 mhos

R = 4.45 ohms

I = V / R

The total current out of the battery is

I = (9v)/(4.45ohms)

I = 2.02 Amperes

As the total current leaves the battery, it splits into 3 paths, and each resistor gets part of it. The 10ohm resistor gets the most current; the 21ohm resistor gets the least current. After flowing through the resistors, the 3 currents join and add up to 2.02 Amperes again, and the same current returns to the battery.

Each resistor has the same 9v of EMF across it.

4 0

3 years ago

A driver in a 2144 kg car traveling at 15 m/s hits the brakes, coming to a stop in 67 meters. How far would it take the car to s

Komok [63]

1) First, let's calculate the value of deceleration a that the car can achieve, using the following relationship:
$2aS = v_f^2-v_i^2 = -v_i^2$
where S=67 m is the distance covered, vf=0 is the final velocity of the car, and vi=15 m/s is the initial velocity. From this we can find a:
$a= \frac{-v_i^2}{2S}= \frac{-(15m/s)^2}{2\cdot 67 m}=-1.68 m/s^2$

2) Then, we can assume this is the value of acceleration that the car is able to reach. In fact, the force the brakes are able to apply is
$F=ma$
This force will be constant, and since m is always the same, then a is the same even in the second situation.

3) Therefore, in the second situation we have a=-1.68 m/s^2. However, the initial velocity is different: vi=45 m/s. Using the same formula of point 1), we can calculate the distance covered by the car before stopping:
$2aS=-v_i^2$
$S= \frac{-v_i^2}{2a} = \frac{-(45 m/s)^2}{2\cdot (-1.68 m/s^2)}=603 m$

4 0

3 years ago

A (hypothetical) large slingshot is stretched 4.00 m to launch a 440 g projectile with speed sufficient to escape from Earth (11

RSB [31]

Answer:

(A) 3,449,600 N/m

(B) 62,720 poeple

Explanation:

extension of the sling shot (e) = 4 m

mass of projectile (m) = 440 g = 0.44 kg

speed of projectile (v) = 11.2 km/s = 11,200 m/s

average force a person can exert = 220 N