Let’s assume that we can ignore the resistance of the air (as one usual does in physics homework).
The distance ‘s’ traveled by an object under constant acceleration ‘a’ in a time ‘t’ is given by
s = 1/2 a t^2
if the object starts at rest. As t=4 seconds and ‘a’ is the usual 9.81 m/s^2, you can put the numbers in and get
s=8*9.81 m ~78.5m or 78 500 cm
A foot amounts to (as you know) 30.3 cm, so you have to divide the above number by the 30.3cm/ft and get
s ~ 257 ft.
Explanation:
Tell me in simple words what gravitation is.
Answer:
The movement, or a tendency to move, toward a center of gravity, as in the falling of bodies to the earth is called gravitation
Can someone PLEASE HELP ME!!!!!!!!
Examples of mediums that waves can travel through are _______ Select ALL that apply.
A. Air
B. Water
C. Ground
D. Metal
Answer:
air and water
Explanation:
The matter through which a mechanical wave travels is called the medium (plural, media). There are three types of mechanical waves: transverse, longitudinal, and surface waves. They differ in how particles of the medium move when the energy of the wave passes through. The particles in a medium become disturbed and pass on this disturbance to the next one, and so on. So, the disturbance caused by the particles can travel through a medium such as air, ocean water, land, violin strings, Slinky coils, etc. Sound waves can travel through solids, liquids, or gases.
A medium-sized apple provides about 95.0 Calories of energy.
(a) Convert 95.0 Cal to joules.
(b) Suppose that amount of energy is transformed into kinetic energy of a 2.03 kg object initially at rest. Calculate the final speed of the object (in m/s).
(c) If that same amount of energy is added to 3.79 kg (about 1 gal) of water at 21.7°C, what is the water's final temperature (in °C)? The specific heat of water is
c = 4186
J
(kg · °C)
.
A. 95 Cal is equivalent to 397480 J
B. The final speed of the object is 625.78 m/s
C. The final temperature of the water is 46.8 °C
A. Converting 95 Cal to Joules
1 Cal = 4184 J
Therefore,
95 Cal = 95 × 4184
95 Cal = 397480 JThus, 95 Cal is equivalent to 397480 J
B. Determination of the speed of the object
Kinetic energy (KE) = 397480 J
Mass (m) = 2.03 Kg
Velocity (v) =?KE = ½mv²
397480 = ½ × 2.03 × v²
397480 = 1.015 × v²
Divide both side by 1.015
v² = 397480 / 1.015
Take the square root of both side
v = √(397480 / 1.015)
v = 625.78 m/sTherefore, the speed of the object is 625.78 m/s
C. Determination of the final temperature of the water
Mass of water (M) = 3.79 kg
Initial temperature of water (T₁) = 21.7 °C
Specific heat capacity of water (C) = 4186 J/KgºC
Heat (Q) = 397480 J
Final temperature (T₂) =?Q = MC(T₂ – T₁)
397480 = 3.79 × 4186 (T₂ – 21.7)
397480 = 15864.94 (T₂ – 21.7)
Clear the bracket
397480 = 15864.94T₂ – 344269.198
Collect like terms
397480 + 344269.198 = 15864.94T₂
741749.198 = 15864.94T₂
Divide both side by 15864.94
T₂ = 741749.198 / 15864.94
T₂ = 46.8 °CTherefore, the final temperature of the water is 46.8 °C
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In this closed system, a dog has sprinted to the top of a cliff. The dog (mass of 25kg) had been sprinting with a velocity of 13m/s. Using what you know about potential and kinetic energy in systems, how tall is the cliff?
Given:
mass =
height =
velocity =
Formula for a closed KE/PE system:
Plug in the numbers:
Answer (with Units):
Please i really need help on this
Which statement is true?
A. Magnetic North is geographic North
B. A compass needle points south
C. Magnetic electrons flow out North and into South
D. Earth's magnetic field reaches past the Milky Way.
(A magnetic compass does not point to the geographic north pole. A magnetic compass points to the earth's magnetic poles, which are not the same as earth's geographic poles. Furthermore, the magnetic pole near earth's geographic north pole is actually the south magnetic pole. When it comes to magnets, opposites attract.)
eeg measures the synchronous electrical activity of the _____.
An athlete spins in a circle and throws a 1.6-kg discus. The radius of the discus's path is 1.0 m, and he releases it with an angular speed of 15.0 rad/s. The athlete spins for a total of 1.2 s before releasing the discus.
– What is the tangential speed of the discus at release?
– What is the centripetal acceleration of the discus?
– What is the centripetal force on the discus?
giving Brainliest for full and proper answers! thank you for anyone who tries to help/explain :)
(a) The tangential speed of the discus at the release is 15 m/s.
(b) The centripetal acceleration of the discus is 225 m/s².
(c) The centripetal force on the discus is 360 N.
The given parameters;
mass of the discus, m = 1.6 kgradius of the path, r = 1 mangular speed, ω = 15 rad/stime of motion, t = 1.2 sThe tangential speed of the discus at the release is calculated as follows;
[tex]v = \omega r\\\\v = 15 \ rad/s \ \times 1 \ m\\\\v = 15 \ m/s[/tex]
The centripetal acceleration of the discus is calculated as follows;
[tex]a_c = \frac{v^2}{r} \\\\a_c = \frac{15^2}{1} \\\\a _c = 225 \ m/s^2[/tex]
The centripetal force on the discus is calculated as follows;
[tex]F_c = ma_c\\\\F_c = 1.6 \times 225\\\\F_c = 360 \ N[/tex]
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Explain how bats use ultrasound to catch a prey
Answer:
Ultrasound is used by bats to navigate (move) and catch prey. Ultrasonic squeaks are produced by bats. These squeaks ponder prey and then return to the bat's ear. This provides bats with information about the location of prey, allowing them to catch it.
Explanation:
The force of gravity between two students is 3.5E-8 Newtons. If
the first students mass is 71.0 kg and the second students mass is
67.0 kg, how far apart must the students be from each other?
Answer:
r = 9521.29
Explanation:
Given:
Gravitational Force = [tex]3.5E-8[/tex] (Fg)
Student Mass 1 = 71 kg (M)
Student Mass 2 = 67kg (m)
Gravitational constant = [tex]6.67E-4[/tex] (G)
[tex]Fg=\frac{GMm}{r^{2} }[/tex]
[tex]r^{2} =\frac{GMm}{Fg}[/tex]
[tex]r^{2} =\frac{(6.67E-4)*(71)*(67)}{3.5E-8}[/tex]
[tex]r= \sqrt{90654828.57}[/tex]
[tex]r=9521.282927[/tex]
r = 9521.29
name two possible ways in wivh fossils can be dated and define them
Answer:
There are two main methods determining a fossils age, relative dating and absolute dating. Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.
Mark me with a crown
Answer: dna
Explanation:
sorry if this is wrong lol
The symbols used in language have no direct relationship between the word and the object or idea.
Answer:
The symbols used in language have no direct relationship between the word and the object or idea. Underextension in language occurs when a child incorrectly uses one word to describe other objects or actions that are similar to that word. ... Morphemes are the smallest distinctive sound units in a language.
Explanation:
Answer:
True
Explanation:
e2021
is there friction when an object stands still?
Answer:
No
Explanation:
The gravitational force always acts opposite the direction of motion. Air resistance only acts on objects that are moving. The force of friction does not exist when an object is stationary. All objects experience a normal force.
btw pls mark as branliest! Thanks!
A 15-volt power supply is used to power a circuit with two resistors in series. The voltage drop across R1 is 5 volts. What is the voltage drop across R2?
5 volts
20 volts
10 volts
0 volts
A 10-volt power supply is used to power a circuit, producing a current of 2 A. If total resistance of circuit is doubled, how will this affect the circuit?
A. Voltage drop across each resistor will all double to match change in resistance
B. The current will change so that the voltage drop for a complete loop through the circuit becomes 5 V.
C. The current will change so that the voltage drop for a complete loop through the current remains at 10 V.
D. The voltage drop across each resistor will be unaffected because each will remain at 0 V
(1) The voltage drop in the second resistor is 10 V.
(2) The voltage drop across each resistor will all double to match change in resistance.
The given parameters:
voltage in the circuit, V = 15 Vvoltage drop in first resistor, V1 = 5 VThe total voltage in a series circuit is given as;
[tex]V_T = IR_1 + IR_2\\\\V_T = V_1 + V_2[/tex]
The voltage drop in the second resistor is calculated as follows;
[tex]V_2 = V_T - V_1\\\\V_2 = 15 - 5\\\\V_2 = 10 \ V[/tex]
(2)
voltage supply, V = 10 Vcurrent, I = 2 AThe resistance of the circuit:
[tex]R = \frac{V}{I} = \frac{10}{2} = 5 \ ohms[/tex]
When the total resistance is doubled;
In series circuit, the current in each resistor is constant, the voltage drop is calculated as;
[tex]V = IR\\\\V = 2 (5+5)\\\\V = 20 \ V[/tex]
Thus, we can conclude that the voltage drop across each resistor will all double to match change in resistance.
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a Name the store of energy when you are
pressing downwards on the stretchy skin
of the trampoline
what’s the energy of motion
A.thermal energy
B. temperature
C. heat
D. kinetic energy
E.potential energy
Answer:
D. Kinetic energy
hope this helps
Answer:
D. Kinetic energy
Explanation:
The combination of kinetic energy and potential energy is known as mechanical energy
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A rock is thrown upward with a speed of 2.0m/s.
a. How long will it take the rock to reach the peak?
b. What is the maximum height it can reach?
Hi there!
(A)
When the rock reaches the peak, it will have a vertical velocity of 0 m/s. We can use the equation:
vf = vi + at
vf = final velocity (0 m/s)
vi = initial velocity (2 m/s)
a = acceleration (in this situation, due to gravity = 9.8 m/s²)
t = time (s)
0 = 2 + (-9.8)t
2/9.8 = t = .204 sec
(B)
Use the equation:
d = vit + 1/2at²
d = 2(.204) + 1/2(-9.8)(.204²)
d = .204 m
A 10 kg box is motionless on the floor. If the coefficient of static friction is 0.4 and
the coefficient of kinetic friction is 0.3 (between the box and the floor), find the
force required to start the block in motion
The force required to start the given box in motion is 39.2 N.
The given parameters;
mass of the box, m = 10 kgcoefficient of static friction, [tex]\mu_s[/tex] = 0.4coefficient of kinetic friction [tex]\mu_k[/tex] = 0.3The force required to start the box in motion must be greater or equal to static frictional force.
The magnitude of the force is calculated as follows;
[tex]F = \mu_s F_n\\\\F = \mu_s mg\\\\F = (0.4) \times (10) \times (9.8)\\\\ F = 39.2 \ N[/tex]
Thus, the force required to start the box in motion is 39.2 N.
Learn more here:https://brainly.com/question/4515354
Answer:
Explanation:
uk=0.3
us==00.4
f=10
ground acceleration =9.8
f=10×0.4×9.8=39.2
Help with this physics
Please
Answer:
45555555555555555555
Explanation:
Could someone please help me
Answer:
the size of the shadow will be smaller due to smaller hands
Công thức tính gia tốc hướng tâm trong chuyển động tròn đều
a. aht = v2/R. B. aht = v2R. C. aht = 2R. C. aht = 42f2/R.
Answer:
I am really sorry but I can't understand the question.
Can you translate the question to English?
Explanation:
Jorge is driving along Route 120 at a speed of 25 m/s. Seeing a red light ahead, he applies the brakes and comes to rest in 3.7 seconds. What is
his rate of acceleration?
Answer:
I don't know...
I'm sorry
4. A net force of 15 N is exerted on a book to cause it to accelerate at a rate of 5 m/s2. Determine the mass of the
book.
a. 0.33 kg
b. 2 kg
c. 3 kg
d. 45 kg
Answer:
3 kgExplanation:
The mass of an object given it's force and acceleration can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{15}{5} = 3 \\ [/tex]
We have the final answer as
3 kgHope this helps you
Are these pictures below an example of reflection or refraction?
Answer:
Refraction
Explanation:
Reflection involves a change in direction of waves when they bounce off a barrier.
Refraction of waves involves a change in the direction of waves as they pass from one medium to another.
Please mark as brainliest if this helps! :)
Which vehicle will have more kinetic energy, a parked
semitruck or a car moving at 50 km/h?
Answer:
a semi truck
Explanation:
Look at the circuit below. What is the potential difference across lamp 2?
The potential difference across lamp #2 is 4.5 volts.
9.(7 +1) Line I 9.7 +9.1 Line 2 The expression was rewritten using the Distributive Property 9. (7 + 1) equals 9. 7 which equals 63 9.7+ 9.1 equals 7 + 1 which equals 63. Submit Answer attempt 1 out of Privacy Policy Terms of Service
Answer:
Sorry
Explanation:
I really don't know what to say about this question I am not sure what to say about this
17. Explain how to calculate the density of an irregular shaped object such as a
rock.
Your
answer
Answer:
Q andA : Density of an irregular shape
1: the density of something is just th mass divided by the volume:D=m\V
2: As described in the previous question the density is given by D= M\V
3: the density just means how much mass per volume.
calculate the mass of the earth if the radius of the earth is 6.38 × 10^6
Answer:
C
Explanation:
C is i thing
Highest common factor of 12r and 10
I think the number 2, not sure
What is the power of a crane that lifts a 120 N load 14 m in 3.6 s?
Answer:
1000n
Explanation:
hop it helps
Answer:
467 watts
Explanation:
Power is = to work/time. Work is = to force (N) times distance from starting point. So first, calculate work. 120N x14m , which is equal to 1680 joules. so then plug it into your power formula. 1680 joules/ 3.6 seconds= 466.666...7, which rounds to 467 watts.
