The resultant of two vectors is maximum, when angle between them is:

A 230.-mL sample of a 0.240 M solution is left on a hot plate overnight; the following morning, the solution is 1.75 M. What vol

Gwar [14]

Answer:

The volume of water evaporated is 199mL

Explanation:

Concentration is calculated with the following formula

$C=\frac{n}{V}$

where n is the number of moles of solute and V is the volume of the solution (in this case is the same as the solvent volume) in liters.

So we isolate the variable n to know the amount of moles, using the volume given in liters

$230mL=0.23L$

$n=C*V=0.240 M*0.23L=0.055 mol$

Now, we isolate the variable V to know the new volume with the new concentration given.

$V=\frac{n}{C} =0.055mol/1.75M=0.031L=31mL$

Finally, the volume of water evaporated is the difference between initial and final volume.

$V_{ev}= V_{i} -V_{f} =230mL-31mL=199mL$

4 0

3 years ago

Two different charges, q1 and q2, are placed at two different locations, one charge at each location. The locations have the sam

Mars2501 [29]

Answer:

No

Explanation:

Electric potential is the work done to bring a unit of charge (1 C) from infinity to a point inside an electric field.

Electric potential energy of a charge q is the energy required to keep it in an electric potential V. Electric potential energy is given by,

U = qV

Hence even if the two charges are on an equipotential surface (surface where the potential is the same at all points), the potenial energy will be different if the magnitude or nature of the charges are different.

5 0

3 years ago

a machine uses a force of 250 newtons to move an object 20 meter in 5 seconds. What is the power of the machine?

nikitadnepr [17]

Answer:

P = 1000J/s

Explanation:

P = W÷ t

P = ( 250N × 20M ) ÷ 5s

P = 5000J ÷ 5s

P = 1000J/s

5 0

3 years ago

There are 15 water molecules in the air, and the relative

AlexFokin [52]

30 30 30 30 30 30 30 30 30 30

6 0

2 years ago

Squids and octopuses propel themselves by expelling water. They do this by keeping water in a cavity and then suddenly contracti

Goshia [24]

Answer:

6.78571 m/s

55.13387 Joules

Explanation:

$v_s$ = Velocity of squid = 2.5 m/s

$v_w$ = Velocity of water

$m_w$ = Mass of water = 1.75 kg

Mass of squid

$m_s=6.5-1.75=4.75\ kg$

Momentum of squid

$p_s=m_sv_s\\\Rightarrow p_s=4.75\times 2.5\\\Rightarrow p_s=11.875\ kgm/s$

As the momentum of the system is conserved

$p_s+p_w=0\\\Rightarrow p_s=-p_w\\\Rightarrow 11.875=-p_w\\\Rightarrow 11.875=-m_wv_w\\\Rightarrow v_w=-\frac{11.875}{1.75}\\\Rightarrow v_w=6.78571\ m/s$

The speed of the water is 6.78571 m/s

Kinetic energy the squid creates is given by

Kinetic energy of the squid + Kinetic energy of water

$K=K_s+K_w\\\Rightarrow K=\frac{1}{2}(m_sv_s^2+m_wv_w^2)\\\Rightarrow K=\frac{1}{2}(4.75\times 2.5^2+1.75\times 6.78571^2)\\\Rightarrow K=55.13387\ J$

Kinetic energy the squid creates by this maneuver is 55.13387 Joules

7 0

3 years ago