Answer:
The correct answer is A. Crossing over occurs
If it takes 820 Joules of heat to warm a sample of zinc from 0°C to 50°C, what would be the mass of the zinc? Note: Zinc has a specific heat of 380 J/kg °C.
Answer:
m = 43.1 g
Explanation:
Given that,
Heat to warm the sample, Q = 820 J
Initial temperature = 0°C
Final temperature = 50°C
The specific heat of zinc is, c = 380 J/kg °C
We need to find the mass of the zinc. The specific heat in terms of mass and temperature is calculated by the relation as follows :
[tex]Q=mc\Delta T\\\\m=\dfrac{Q}{c\Delta T}\\\\=\dfrac{820}{380\times (50-0)}\\\\=0.0431\ kg\\\\=43.1\ g[/tex]
So, the mass of the sample is 43.1 g.
Answer:
43.1 g
Explanation:
A pendulum is transported from sea-level, where the acceleration due to gravity g is 9.80 m/s2, to the bottom of Death Valley. At this location, the period of the pendulum is decreased by 3.00%. What is the value of g in Death Valley
Answer: the value of g in Death Valley is 10.417 m/s²
Explanation:
Given that;
acceleration due to gravity at the point is g = 9.8 m/s²
Lets say the acceleration due to gravity at the bottom of Death valley is g'
as the period of the pendulum is decreased by 3.00%
T' = 0.97 T
T is the period of the pendulum at sea level and T' is the period of the pendulum at bottom of Death valley
therefore from the relation
T = 2π√(l/g)
g'/g = T²/T'²
g' = (T²/ (0.97T)²)g
g' = 1.063g
g' = 10.417 m/s²
therefore the value of g in Death Valley is 10.417 m/s²
Which direction of motion is affected by gravity?
Answer:
Gravity can also cause an object that is thrown into the air to change its upward motion, slow down, and fall back toward Earth's surface. The pull of Earth's gravity keeps the Moon in orbit; the moon is constantly changing direction because of gravity.
The gravitational field or gravitational potential has no direction; it's just a value that varies from place to place and over time.
Explanation:
PLEASE HELP THIS IS TIMED
John pushes forward on a car with force of 300 N while Bob pushes backward on the car with a force of 385 N. What is the net force on the car?
A. 85 N backward
B. 685 N backward
C. 685 N forward
D. 85 N foward
Answer:
85 N backwards
Explanation:
u subtract then thats the net force and add direction
When are zeros significant when found in front of (to the left) of the decimal point?
Answer:
If a zero is found between important digits, it is important. Zeros are also used as (not salient) holders to the left of digits if the number is in fact a decimal. Example from www.rpi.edu: , a mass of 42 g has two significant digits. Expressed in kilograms, the mass of 0.042kg should still have two significant digits.
Explanation:
Zeros are also used as (not salient) holders to the left of digits if the number is in fact a decimal. Example from www.rpi.edu: "A mass of 42 g has two significant digits. Expressed in kilograms, the mass of 0.042kg should still have two significant digits."
Hope this comes in handy, have a great day!
it is not uncommon for us to hold stereotypes toward people. The main advantage of forming a stereotype is that it______. The main disadvantage is that it_____.
Answer:
It is not a me mental shortcut
Explanation:
Can be changed easily
It is not uncommon for us to hold stereotypes toward people. The main advantage of forming a stereotype is that they make fast and quick decision. The main disadvantage is that they make generalized decision.
Who is a stereotype person?A stereotype is a persistent, vastly oversimplified view about a particular group or category possesses. A stereotype person make his own belief for the peoples.
A stereotype has the advantage of allowing us to respond quickly to events, since we may have had a similar experience before.
One negative is that it causes us to overlook individual distinctions, leading us to believe things about others that are not always true.
It is not uncommon for us to hold stereotypes toward people. The main advantage of forming a stereotype is that they make fast and quick decision. The main disadvantage is that they make generalized decision
The correct option for the blanks are make fast and quick decision and generalized decision.
To learn more about the stereotype, refer to the link;
https://brainly.com/question/13281670
#SPJ2
An automobile accelerates uniformly from a speed of 60 km/hr (16.67 m/s) to a speed of 80 km/hr (22.2 m/s) in 5 s. Determine the acceleration of the car and the distance traveled in this 5 sec interval.
Answer:
The acceleration is [tex]1.106\ m/s^2[/tex] and the distance covered is 97.17 m.
Explanation:
Given that,
Initial speed of an automobile, u = 60 km/hr = 16.67 m/s
Final speed of an automobile, v = 80 km/hr = 22.2 m/s
Time, t = 5 s
We need to find the acceleration of the car and the distance traveled in this 5 sec interval. Let a is the acceleration. Using the definition of acceleration as :
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{22.2-16.67}{5}\\\\a=1.106\ m/s^2[/tex]
Let d is the distance covered. Using the third equation of motion to find it as follows :
[tex]v^2-u^2=2as\\\\s=\dfrac{v^2-u^2}{2a}\\\\s=\dfrac{(22.2)^2-(16.67)^2}{2\times 1.106}\\\\s=97.17\ m[/tex]
So, the acceleration is [tex]1.106\ m/s^2[/tex] and the distance covered is 97.17 m.
Which is NOT a property of the organisms that have become useful index fossils
Answer: I dont understand
Explanation:
In an experiment, a research collected the following informationabout a solution made from a certain
food. What can we conclude about the food?
• pH = 3.0
• Taste = Sour
A. Acid
B. Base
C. Neutral
D. Salt
Answer:
salt
Explanation:
How were Native American political systems the same or different from other civilizations?
Answer:
Tribal governments were much smaller and were usually more local. Anyone could have a voice in making political decisions. In most cases, important decisions were made by majority rule. This means that the group would take a vote. The decision that got the most votes would win.
Tribal leadership was local too. It depended mostly on a person’s wisdom and skills. As a result, leaders changed frequently. Some tribes chose one chief to lead in peacetime and another to lead during war. Custom and tradition governed the people’s actions, not written laws.
Explanation:
This is what i used for my DBA hope its helps you!
(on FLVS btw)
Walking down a pebble beach becomes less painful as you enter the sea. Explain why.
Answer:Since pressure = force/area, the same force on a smaller area means more pressure. When you are walking on sand, the force being applied by your body is spread out over the entire surface of your foot. ... So, more pressure applied on a given area of your foot causes more pain.
Explanation:
Good Question
Q17: The coefficient of linear expansion of steel is a = 11 x 10-6 / °C. A steel
ball has a volume of exactly 100 cm3 at 0°C. When heated to 100°C, its
volume becomes in (cm3):
A
B
D
E
100.33
100.11
100.0011
100.0033
None of them
Solution:
The coefficient of volume expansion
p = ΔV/V1Δt
3a = V2-V1/V1Δt
Given
a = = 11 x 10-6 / °C
V2 is the final volume
V1 is the initial volume = 100cm³
Δt = 100-0 = 100°C
Substitute
3(11 x 10-6) = V2-100/100(100)
33*10^-6 * 10000 = V2-100
33*10^-2 = V2-100
V2 = 100 + 0.33
V2 = 100.33
Hence the new volume is 100.33cm³
4). A basketball player shoots the ball in the air. It moves through the air
at 20 m/s and travels 25m. How long was the ball in the air? *
Let's start from this equation:
s = vt + s0
Know what it is? Of course you do. It's the equation used for knowing the position of an object in a certain period of time t.
s is space, v is speed, t is time, s0 is the initial space.
In this case the initial space is equal to 0 so our equation will become:
s = vt
Let's find t:
t = s/v
So:
t = 25m/20m/s = 1,25 s
---
Hope it was helpful. Have a great day!
Left Force
150N
50N Right Force
Calculate the net force acting on the object. Show your work and be sure to
clude the correct unit.
Answer:
100 N to the left
Explanation:
Left force:150 N
Right force:50 N
So 150 - 50 = 100 N
Since the left force is greater, the resultant force is to the left
When a balloon is rubbed on a surface and then touched to hair it will attract the hair, causing it to stick to the balloon. Explain why this happens.
Answer:
electricity
Explanation:
Answer:
This is called static electricity
Explanation:
The reasoning behind this is because the negative electrons in your hair are being transferred to the balloon, then when the balloon is removed it pulls on the hair with an attractive electric force.
Sean, whose mass is 60 kg, is riding on a 5.0 kg sled initially traveling at 8.0 m/s. He brakes the sled with a constant force, bringing it to a stop in 4.0 s. What force does he apply?
Answer:
130NExplanation:
according to Newtons second law;
F = ma
F = m(v-u)/t
m is the mass = 60+5 = 65kg
v is the final velocity = 0m/s
initial velocity = 8m/s
time t = 4.0s
F = 65(8)/4
F = 65*2
F = 130N
Hence he applied a force of 130N
A student builds an electromagnet using a battery, an iron nail, and some insulated wire. The wire is wrapped around the nail 50 times, then connected to the
battery. What changes could the student make to increase the strength of the electromagnet?
1. wrap more wire around the nail
2. increase the voltage of the battery
3. use a switch to turn the electromagnetic on and off
4. increase the size of the nail
A. 1 and 2
B. 2 and 4
C. 1,2 and 4
D. 1,2,and 3
Answer:
a
Explanation:
its right
To increase the electromagnet's strength, the student must enlarge the nail, wrap more wire around the nail, and increase the voltage of the battery. Option c is the correct answer.
How does an electromagnet work?The mechanics of an electromagnet are not overly complicated. It is accomplished by wrapping a length of conductive wire, usually copper, around a metal object.Until electricity is introduced, this appears to be nothing more than a jumbled collection of parts, similar to Frankenstein's monster. An electromagnet, on the other hand, does not require a storm to be activated. A current is introduced and flows through the wire, which can come from a battery or another source of power.As a result of the magnetic field created around the coiled wire, the metal is magnetized as if it were a permanent magnet. Electromagnets are useful because they can be activated and deactivated by closing and opening a circuit.To learn more about electromagnet, refer to
brainly.com/question/7382276
#SPJ2
What is the freezing point (in degrees Celcius) of 4.67 kg of water if it contains 171.9 g of C a B r 2
Answer:
c
Explanation:
changes from a liquid to a solid
At what condition does a body becomes weightless at the equator?
Answer:
The decrease is due to the bulge at the equator (putting more distance between the rest of the planet and the surface
Explanation:
angle of reflection
The angle of reflection equals the angle of Incidence
Explanation:
The Law Of Reflection
A heavy bank-vault door is opened by the application of a force of 300 N directed perpendicular to the plane of the door at a distance of 0.80 m from the hinges. What is the torque?
Question 4 options:
1.) 120 Nm
2.) 240 Nm
3.) 375 Nm
4.) 300 Nm
Answer:
240Nm
Explanation:
Given parameters:
Force on the bank vault = 300N
Distance to the plane of the vault = 0.8m
Unknown:
Torque = ?
Solution:
Torque is the component of force that causes an object to rotate about an axis;
Torque = Fr x sinФ
Here Ф = 90°
r = distance
Torque = 300 x 0.8 x Sin 90°
Torque = 240Nm
Whats the mass of air in a room if the floor dimensions are 10 m × 12 m and height 4m. The density of air is 1.26 kgm
Answer:
604.8
Explanation
I multiplied density and volume
Rocks that do not allow water to pass through them are said to be impermeable. True or false?
Answer:
true plz mark me as the brainliest
Explanation:
Answer:
TrueSome rocks have pores in them, which are empty spaces. If these pores are linked then fluid can flow through the rock.However,if the pores are not linked,then no liquid can flow through the rocksWhen pores are not linked,the rock is permiable.n
what energy transfer will a stretched rubber band have when let go
Answer:
when the rubber band is realeased the potential energy is quickly converted to kinetic energy this is equal to one mass of the the rubber band multiplied by its velocity( in meters per second)
Some examples from everyday life of thermal radiators include:______.A. Humans.B. The Sun.C. Incandescent light bulbs.D. Lasers.E. Accelerating electrons.
Answer: A. Humans B. The sun C. Incandescent light bulbs
Explanation:
Thermal radiators are simply referred to as the heat exchangers that are designed in order to transfer thermal energy from one particular place to another.
Some examples from everyday life of thermal radiators include humans, the Sun and incandescent light bulbs. All these help in transfer of hear from one medium to another medium
Is a compound considered a pure substance?
Answer:
It depends on which compound you use carbon dioxide can be while helium will not but if you where to sum it up it would be use because simply most compounds are considered pure substance.
Explanation:
A 300 g object attached to a horizontal spring moves in simple harmonic motion with a period of 0.340 s. The total mechanical energy of the spring–object system is 3.00 J.
(a) What is the spring constant (in N/m)?
(b) What is the amplitude (in m) of the motion?
(c) What is the percentage change in amplitude of motion if the total energy of the system is increased to 5.00 J?
Answer:
Explanation:
angular velocity ω = 2π / T where T is time period of rotation .
= 2 x 3.14 / .34 = 18.47 rad /s
Total mechanical energy = 1/2 m ω²Α² where A is amplitude .
spring constant = k
[tex]\omega=\sqrt{\frac{k}{m} }[/tex]
m is mass
[tex]\omega^2=\frac{k}{m} }[/tex]
18.47² = k / .3
k = 102.34 N /m
b )
energy = 1/2 m ω²Α²
3 = .5 x 18.47² x A²
A² = .01759
A = .1326
13.26 cm .
c )
If energy becomes 5 J
5 = .5 x 18.47² x A²
A² = .0293
A = .1711
= 17.11 cm
percent increase
= (17.11 - 13.26 )x100 / 13.26
= 29%
Can you help me with this question please
Answer:
9.6 Ω
Explanation:
Notice that this circuit is the same as the one shown in the attached image.
Then we calculate the parallel of R1 and R3 first:
Since R1 = 30 Ω and R2 = 20 Ω, the parallel equivalent of this is 12 Ω and this in series with R5 (4 Ω) is 16 Ω.
Now we calculate the parallel circuit of the three resistors
40 Ω, 60 Ω, and 16 Ω, which gives us: 9.6 Ω
What is the mechanical advantage of a nail puller where you exert a force 45 cm from the pivot and the nail is 1.8 cm on the other side? What minimum force must you exert to apply a force of 1250 N to the nail?
Answer:
Explanation:
Mechanical Advantage is the ratio of the distance of the input load (Li)from the pivot to the output load applied to the pivot(Lo)
MA = Li/Le
Given;
Li = 45cm
Lo = 1.8cm
MA = 45/1.8
MA = 25
Hence the mechanical advantage is 25
Also MA is expressed in terms of the force ratio which is the ratio of the Load to the effort applied.
MA = Load/Effort
Given
Load = 1250N
MA = 25
Effort = ?
Substitute
25 = 1250/Effort
Effort = 1250/25
Effort = 50N
Hence the minimum force exerted on the load is 50N
Imagine that you drop an object of 10 kg, how much will be the acceleration and
how much force causes the acceleration?
If you do this on Earth, then the acceleration of the falling object is 9.8 m/s^2 ... NO MATTER what it's mass is.
If its mass is 10 kg, then the force pulling it down is 98.1 Newtons. Most people call that the object's "weight".