Explanation:
Chem has to do with stored energy while nucleic deals with nucleic reactions.
given that two vectors A=i,2j-2k and B=6i+3j+2k find A +B
Answer:
7i, 5j, 0k
Explanation:
Add up the two vectors.
Add
i+i 1+6 = 7i
j+j 2+3 = 5j
k+k -2+2 = 0k
therefore A+B = (7i, 5j, 0k)
Gaseous sulfur dioxide is a compound that combines with water in the atmosphere to form acid rain. What is the primary source of sulfur dioxide?
O volcanic emissions
O combustion of fossil fuels
O destruction of tropical forests
O mining and mineral extraction
help, it's an emergency !!!!!!!
What happens when you move two
objects far apart from each other?
A. The force of gravity increases.
B. The force of gravity decreases.
C. Distance does not affect the force of gravity.
D. The friction between the two objects will increase.
Answer:
b
Explanation:
who compose the Ghana national anthem
Answer:
Philip Gbeho
Explanation:
A) how many cm³ are there in 0.08L?
B) How many dm³ are there in 750mL?
Answer:
A) 80 cm³
B) 0.75 dm³
Explanation:
I hope this help❤️
Three 5 Ohm resistors are connected in parallel to a 9 Volt power supply. What is the current through each resistor?
Answer:
I₁ = I₂ = I₃ = 12 A
Explanation:
Since the resistors are connected in parallel across a battery. Hence, the voltage across each of them will be the same, which will be equal to the voltage of the power supply. Since each resistor has the same resistance of 5 Ω. Therefore. the current across each resistor will also be the same. We can easily calculate these current values by the use of Ohm's Law, as follows:
[tex]V = IR\\I_{1}=I_{2}=I_{3}=\frac{V}{R} \\\\I_{1}=I_{2}=I_{3}=\frac{9\ Volt}{5 \Omega}\\\\[/tex]
I₁ = I₂ = I₃ = 12 A
TOINETS
Assuming that distances are
equal, which of the following
objects would have the MOST
gravitational force with you?
A. Jupiter
NETTUNE
B. Earth
UNIVERSE
C. Sun
Answer:
The sun.
Explanation:
The sun has the most gravitational pull.
What is Na2SO4?
Help pleaseeee.
A human body consists of
Answer:
60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, the brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%.
Explanation:
Which of the following is a conductor?
copper
water
aluminum
all of the above
Answer:
D all of the above
Explanation:
electricity moves easily through all of them and none of them prevent the flow of electricity
Please help
The period of an oscillation is measured to be 0.0833 seconds. What is
the frequency of this oscillation? *
1.0833 Hz
0.287 Hz
9.8 Hz
12 Hz
0.007 Hz
Answer:
your
answer is
12.004
PLZ HELP PLZ ILL GIVE BRAINLIEST TO BEST ANSWERED
The Earth's gravity pulling on a skydiver: Contact or Non Contact
Friction from a car's brakes causing it to stop: Contact or Non Contact
The repulsive magnetic force between the north poles of two magnets: Contact or Non Contact
The attractive electrostatic force between an electrically charged balloon and a wall: Contact or Non Contact
Answer:
1.Contact because its a contact force
2 Contact because when the car is stopping it is coming in to contact with the ground.
3 non Contact because magnets don't need to have contact they pull
4 non Contact because its not a contact force
You want to use a metal bar as a resistor. Its dimensions are 1 by 3 by 13 units. To get the largest resistance from the bar, you should attach leads to the two opposite sides that have dimensions of 1 by 3 units. All configurations give the same resistance. 3 by 13 units. 1 by 13 units. None of the above.
Answer:
1 by 3 units
Explanation:
The resistance (R) of a conductor is given by the formula:
R = ρL / A
where L is the length of the conductor, ρ is resistivity and A is the cross sectional area.
Let us assume that the metal bar has a resistivity of ρ.
a) If the leads is attached to the two opposite sides that have dimensions of 1 by 3 units.
The length of the bar would be 13 units and the cross sectional area (A) would be = 1 * 3 = 3 units²
R₁ = ρL / A = ρ(13) / 3 = 13ρ / 3
b) If the leads is attached to the two opposite sides that have dimensions of 3 by 13 units.
The length of the bar would be 1 units and the cross sectional area (A) would be = 3 * 13 = 39 units²
R₂ = ρL / A = ρ(1) / 39 = ρ / 39
c) If the leads is attached to the two opposite sides that have dimensions of 1 by 13 units.
The length of the bar would be 3 units and the cross sectional area (A) would be = 1 * 13 = 13 units²
R₃ = ρL / A = ρ(3) / 13 = 3ρ / 13
Therefore we can see that the largest resistance is gotten If the leads is attached to the two opposite sides that have dimensions of 1 by 3 units
How much work is done by 15 kW engine during 3.5 min? Explain the answer if you can plz
Answer:
W = 3.15 · 10⁶ J
Explanation:
We know that power is calculated using the formula:
P = W/twhere P = power (W), W = work (J), and t = time (s)We can derive a formula for work using this formula by multiplying t to both sides of the equation.
W = PtLet's convert 15 kW to W.
15 kW → 15,000 WLet's convert 3.5 min to s.
3.5 min → 210 sSubstitute these values into the formula for work and solve for W.
W = Pt W = (15,000 W) · (210 s) W = 3,150,000 J W = 3.15 · 10⁶ JThis is the amount of work done by a 15 kW engine in 3.5 minutes.
A projectile is thrown with a velocity of 40 m/s, 45 degrees above the +x-axis. Determine its initial x-velocity and its initial y-velocity.
x-component is V·cos(angle)
y-component is V·sin(angle)
When the angle is 45°, its sin and cos are both 1/2·√2 .
Vx = 20·√2 = 28.28 m/s
Vy = 20·√2 = 28.28 m/s
PLEASE HELP ME WITH ONE QUESTION
If 1000 J of heat energy is lost from a piece of hot metal which is placed into a cup of cool water, how much energy is gained by the water?
Answer:
1000J
Explanation:
According to the law of calorimetry;
Heat lost by cold substance = Heat gained by hot substance
If 1000 J of heat energy is lost from a piece of hot metal,
heat lost by hot substance = 1000J
Since we are to determine how much energy is gained by the water, using the law
Heat lost by hot metal = heat gained by the water
Hence heat gained by the water = 1000J
Two resistors R1 = 3 Ω and R2 = 6 Ω are connected in parallel. What is the net resistance in the circuit?
Answer:
2ohms
Explanation:
the net resistance is given by
1/R=1/R1 +1/R2,we are supposed to find R
thus by making R the subject ....
R=R1•R2/R1+R2
R=3•6/3+6
R=18/9 =2Ohms
Which types of reactions are also redox reactions?
Answer:
Your ans is B)
Explanation:
Hope its right
if wrong firgive me
A uniform 140 g rod with length 57 cm rotates in a horizontal plane about a fixed, vertical, frictionless pin through its center. Two small 30 g beads are mounted on the rod such that they are able to slide without friction along its length. Initially the beads are held by catches at positions 11 cm on each sides of the center, at which time the system rotates at an angular speed of 23 rad/s. Suddenly, the catches are released and the small beads slide outward along the rod. Find the angular speed of the system at the instant the beads reach the ends of the rod. Answer in units of rad/s.
Answer:
The correct answer is "12 rad/s"
Explanation:
The given values are,
Mass of rod,
M = 140 g
i.e.,
= 0.14 kg
Length,
L = 57 cm
i.e.,
= 0.57 m
Mass of beads,
M = 30 g
i.e.,
= 0.03 kg
Angular speed,
r = 11 cm
i.e.,
= 0.11 m
Now,
The inertia of rods will be:
= [tex]\frac{1}{12}ML ^2[/tex]
On substituting the values, we get
= [tex]\frac{1}{12}\times 0.14\times (0.57)^2[/tex]
= [tex]0.0037905 \ kg-m^2[/tex]
The inertia of beads will be:
= [tex]mr^2[/tex]
On substituting the values, we get
= [tex]0.03\times (0.11)^2[/tex]
= [tex]0.000726 \ kg-m^2[/tex]
The total inertia will be:
= [tex]Inertia \ of \ rods+Inertia \ of \ beads[/tex]
= [tex]0.0037905 + 0.000726[/tex]
= [tex]0.0045165 \ kg-m^2[/tex]
now,
The angular speed of the system will be:
⇒ [tex]L_1w_1=L_2w_2[/tex]
On substituting the values in the above equation, we get
⇒ [tex]0.0045165\times 23 = (0.0037905 + (0.03\times 0.285^2)\times 2 )\times w_2[/tex]
⇒ [tex]0.1038795 = 0.0037905 + (0.00243675\times 2 )\times w_2[/tex]
⇒ [tex]w_2 = 12 \ rad/s[/tex]
Suppose that 2 J of work is needed to stretch a spring from its natural length of 24 cm to a length of 42 cm. (a) How much work is needed to stretch the spring from 32 cm to 34 cm
Answer:
Workdone = 0.025 Joules
Explanation:
Given the following data;
Workdone = 2J
Extension = 42 - 24 = 18 cm to meters = 18/100 = 0.18m
The workdone to stretch a string is given by the formula;
Workdone = ½ke²
Where;
k is the constant of elasticity.
e is the extension of the string.
We would solve for string constant, k;
2 = ½*k*0.18²
2 = ½*k*0.0324
Cross-multiplying, we have;
4 = 0.0324k
k = 4/0.0324
k = 123.46 N/m
a. To find the workdone when e = 32, 34.
Extension = 34 - 32 = 2 to meters = 2/100 = 0.02m
Workdone = ½*123.46*0.02²
Workdone = 61.73 * 0.0004
Workdone = 0.025 Joules
Therefore, the amount of work (in J) needed to stretch the spring from 32 cm to 34 cm is 0.67.
The microwaves produced inside a microwave have a wavelength of 12.0m and a frequency of 25Hz. At what speed do the microwaves travel in units of m/s ?
Answer: 300 m/s
Explanation:
The equation for finding wave speed is the wavelength times the frequency which would be
12.0mx 25hz=300m/s
Find the velocity of a dolphin that swims 55 m in 5.0 s.
Answer: 11 m/s
Explanation: velocity = distance /time = 55 m /5.0 s
Answer:40km/h
Explanation:
Three cylindrical wires, 1, 2, and 3 are made of the same materialand have resistances R1, R2, and R3, respectively. Wires 1 and 2 have the same lengthbut diameter of wire 2 is twice that of wire 1. Wires 2 and 3 have the same diameterbut length of wire 3is twice that of wire 2.
1. Rank the wires according to their resistances, greatest first.
A. R1> R2> R3R1
B. R1> R3> R2R2
C. R2> R1> R3R3
D. R2> R3> R1
E. R3> R1> R2
F. R3> R2> R1Q2.
2. If same voltage is applied across each of the wires, which one will dissipate heat at the highest rate
Answer:
1) R₁ > R₃ > R₂ correct B , 2) the wire that dissipates the most is wire 2
Explanation:
1) The resistance of a wire is given by the expression
R = [tex]\rho \ \frac{l}{A}[/tex]
where ρ is the resistivity of the material, l the length of the wire and A the area of the wire
The area is given by
A = π r² = π d² / 4
we substitute
R = (ρ 4 /π) [tex]\frac{l}{d^2}[/tex]
the amount in parentheses is constant for this case
let's analyze the situation presented, to find the resistance of each wire
* indicate l₁ = l₂ and d₂ = 2 d₁
the resistance of wire 1 is
R₁ = (ρ 4 /π) [tex]\frac{l_1}{d_1^2}[/tex]
the resistance of wire 2 is
R₂ = (ρ 4 /π) \frac{l_2}{d_2^2}
R₂ = (ρ 4 /π) [tex]\frac{l_1}{ (2 d_1)^2}[/tex]
R₂ = (ρ 4 /π ) [tex]\frac{l_1}{d_1^2}[/tex] ¼
R₂ = ¼ R₁
* indicate that d₂ = d₃ and l₃ = 2 l₂
R2 = (ρ 4 /π) [tex]\frac{l_2}{d_2^2}[/tex]
the resistance of wire 3 is substituting the indicated condition
R3 = (ρ 4 /π 2) \frac{l_3}{d_3^2}
R3 = (ρ 4 /π) [tex]\frac{2 \ l_2}{d_2}[/tex]
R3 = 2 R₂
let's write the relations obtained
R₁ = (ρ 4 /π) [tex]\frac{I_1}{ d_1^2}[/tex]
R₂ = ¼ R₁
R₃ = 2 R₂
let's write everything as a function of R1
R₁ =(ρ 4 /π) [tex]\frac{l_1}{d_1^2}[/tex]
R₂ = ¼ R₁
R₃ = ½ R₁
the resistance of the wire in decreasing order is
R₁ > R₃ > R₂
2) The power dissipated by a wire is
P = V I
the voltage is
V = I R
I = V / R
substituting
P = V² / R
therefore the power dissipated by each wire is
wire 1
P₁ = V² / R₁
wire 2
P₂ = V² / R₂
P₂ = [tex]\frac{V^2}{ \frac{1}{4} R_1}[/tex]
P₂ = 4 P₁
wire 3
P₃ = V² / R₃
P₃ = [tex]\frac{V^2}{ \frac{1}{2} R_1}[/tex]
P₃ = 2 P₁
Therefore, the wire that dissipates the most is wire 2
The amount of sliding friction depends on the
a. weight of the moving object and the type of surface that the
object slides across.
b. density and volume of the object.
c. acceleration and mass of the object.
d. density and mass of the object.
*help please
Answer:
c I think so do u know the formula for friction??friction? lkke kinetic friction
The statement "If a plant receives fertilizer,
then it will grow to be bigger than a plant
that does not receive fertilizer" is an
example of
A. an observation.
B. a hypothesis.
C. a theory.
Changes of
Which now represents the change of state described
above?
M
ham shows changes of state between solid.
se atoms of a substance lase energy
Bacharest Betore the change, the atoms
ether but are able to slide past one another
Answer:b yuh
Explanation:
Yuh
After landing on an unexplored Klingon planet, Spock tests for the direction of the magnetic field by firing a beam of electrons in various directions and by recording the following observations:1. Electrons moving upward feel a magnetic force in the northwest direction.2. Electrons moving horizontally toward the north are pushed downward.3. Electrons moving horizontally toward the southeast are pushed upward.Mr. Spock therefore concludes that the magnetic field at this landing site is in which direction?A) toward the eastB) toward the northeastC) toward the southwestD) toward the southeastE) toward the west
Answer:
the correct one is C,
Explanation:
The magnetic force is given by the expression
F = q v x B
where the bold letters indicate vectors, we can find the modulus of this expression
F = q v B sin θ
The direction of the to the force with the rule of the right hand. The thumb applies in the direction of the speed, the fingers extended in the direction of the magnetic field and if the charge is positive the palm is in the direction of the force, if the charge is megative the force is in the opposite direction to the palm of hand.
Let's analyze the different situations presented; As the particles emitted are electrons, their charge is negative.
Situation 1. The thumb points upwards, the force is towards the NW as the charge is negative, the palm points towards the SE therefore the finger points towards the SOUTHWEST which must be the direction of the magnetic field
Situation 2. the electrons go horizontally to the north the thumb points in this direction, the force is downwards, therefore the palm points upwards, the extended fingers point to the WEST
Situation 3. the thumb points to the SE towards where the electrons move, the force is upwards the palm points to the SW, therefore the fingers extended points SOUTHWEST
As a result of situations 1 and 3 the magnetic field must point in the SOUTHWEST direction.
Situation 2 gives a different result because the component of the field that is directed to the south does not create exerts and therefore cannot be detected.
When checking the answers, the correct one is C
Please please help I'm stuck!!!
Answer: iDc im in 3grade
Explanation:sorry
The desperate contestants on a TV survival show are very hungry. The only food they can see is some fruit hanging on a branch high in a tree. Fortunately, they have a spring they can use to launch a rock. The spring constant is 900 N/m, and they can compress the spring a maximum of 45 cm. All the rocks on the island seem to have a mass of 500 g.
a) With what speed does the rock leave the spring?
b) To what height can the rock be launched?
Answer:
a) v = 18.86 m / s, b) h = 8.85 m
Explanation:
a) For this exercise we can use the conservation of energy relations.
Starting point. Like the compressed spring
Em₀ = K_e + U = ½ k x² + m g x
the zero of the datum is placed at the point of the uncompressed spring
Final point. With the spring if compress
Em_f = K = ½ m v²
how energy is conserved
Em₀ = Em_f
½ k x² + m g x = ½ m v²
v² = [tex]\frac{k}{m}[/tex] x² + 2gx
let's reduce the magnitudes to the SI system
m = 500 g = 0.500 kg
x = -45 cm = -0.45 m
the negative sign is because the distance in below zero of the reference frame
let's calculate
v² = [tex]\frac{900}{0.500}[/tex] 0.45² + 2 9.8 (- 0.45)
v = √355.68
v = 18.86 m / s
b) For this part we use the conservation of energy with the same initial point and as an end point at the point where the rock stops
Em_f = U = m g h
Em₀ = Em_f
½ k x²2 + m g x = m g h
h = ½ [tex]\frac{k}{g}[/tex] x² + x
let's calculate
h = [tex]\frac{1}{2} \ \frac{900}{9.8 } \ 0.45^2[/tex] - 0.45
h = 8.85 m
measured from the point where the spring is uncompressed