Answer:
She is going at 30.4 m/s at the top of the 35-meter hill.
Explanation:
We can find the velocity of the skier by energy conservation:
[tex] E_{1} = E_{2} [/tex]
On the top of the hill 1 (h₁), she has only potential energy since she starts from rest. Now, on the top of the hill 2 (h₂), she has potential energy and kinetic energy.
[tex] mgh_{1} = mgh_{2} + \frac{1}{2}mv_{2}^{2} [/tex] (1)
Where:
m: is the mass of the skier
h₁: is the height 1 = 82 m
h₂: is the height 2 = 35 m
g: is the acceleration due to gravity = 9.81 m/s²
v₂: is the speed of the skier at the top of h₂ =?
Now, by solving equation (1) for v₂ we have:
[tex] v_{2}^{2} = \frac{2mg(h_{1} - h_{2})}{m} [/tex]
[tex] v_{2} = \sqrt{2g(h_{1} - h_{2})} = \sqrt{2*9.81 m/s^{2}*(82 m - 35 m)} = 30.4 m/s [/tex]
Therefore, she is going at 30.4 m/s at the top of the 35-meter hill.
I hope it helps you!
An electron (e = 1.6 x 10-19 C) is traveling at 4.00 x 107 m/s due North in a horizontal plane through a point where the earth’s magnetic field has a component to the North of 2.00 x 10-5 T and a downward (in to the earth) of 5.00 x 10-5 T. Calculate the magnetic force (magnitude and direction) on the electron and its acceleration. Me = 9.11 x 10-31 kg
Answer:
Explanation:
Force on the electron due to magnetic field 's north component will be zero because both velocity of electron and direction of magnetic field are same .
Force due to downward component of magnetic field
= B q v where B is magnetic field , q is charge moving and v is velocity of charge
F = 5 .00 x 10⁻⁵ x 1.6 x 10⁻¹⁹ x 4 x 10⁷
= 32 x 10⁻¹⁷ N
acceleration = F / m where m is mass of electron
= 32 x 10⁻¹⁷ / 9.11 x 10⁻³¹
= 3.5 x 10¹⁴ m/s²
16. A strong acid has a pH close to 7
A.True
B.False
Answer:
I think it's true.
Hope this helps .
Explanation:
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.
Which of the following best describes why tidal energy is considered a renewable energy resource? A. The Moon receives energy from the Sun, which is a renewable resource. B. Humans can create more tidal energy by setting up more tidal energy plants. C. Ocean water will never be exhausted. D. Tidal energy is replaced naturally by the Moon's gravity.
Answer:
D. Tidal energy is replaced naturally by the Moon's gravity.
Explanation:
The reason tidal energy is considered a renewable energy resource is that Tidal energy is replaced naturally by the Moon's gravity. The Moon's gravity creates bulges on the side of Earth that is closest and farthest from the Moon. These bulges also pull water causing high tides in those areas. As the Earth rotates these areas experience low tide while the areas that had low tide now experience high tide. This constant shift creates tidal energy every day, which is replenished naturally.
You serve a volleyball with a mass of 2.5 kg. The ball leaves your hand with a speed of 23 m/s. What is the kinetic energy of the ball?
Answer:
661.25, I believe!
Explanation:
KE = (1/2)(2.5)(23)^2
KE=(1.25)(529)
KE= 661.25
Using Ohms Law, calculate the current that would exist in a circuit having a voltage of 240V experiencing 110 Ohms of resistance
To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)
A baseball is struck home plate and acquires a speed of 60m/s. It rises to a height of 100.0 m above its starting level. Find its speed at the height
Answer:
40 m/s.
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 60 m/s
Height (h) = 100 m
Acceleration due to gravity (g) = 10 m/s²
Final velocity (v) =?
The velocity at height 100 m can be obtained as follow:
v² = u² – 2gh (since the ball is going against gravity)
v² = 60² – (2 × 10 × 100)
v² = 3600 – 2000
v² = 1600
Take the square root of both side
v = √1600
v = 40 m/s
Thus, velocity at height 100 m is 40 m/s
Which statement is false?
A) Doubling the mass halves the acceleration
B) Doubling the force doubles to acceleration
C) Doubling the mass doubles the acceleration
Statement C is false. Doubling the mass doubles the acceleration is the wrong statement.
What is force?Force is defined as the push or pulls applied to the body. Sometimes it is used to change the shape, size, and direction of the body.
Force is defined as the product of mass and acceleration. Its unit is Newton.
Mathematically, the force is;
[tex]\rm F= ma[/tex]
If force is constant, the mass is inversely proportional to the acceleration. If the mass is double in that condition, acceleration is halved.
Doubling the mass doubles the acceleration is the wrong statement.
Hence, statement C is false
To learn more about the force, refer to the link;
https://brainly.com/question/26115859
#SPJ2
Help!!! Please need it fast. If correct I’ll give b
Answer:
if bother parents have brown eyes but they carry the allele for blue eyes a quarter of the kids will have blue eyes and three quarters will have brown eyes. hope this help I'm sorry if it doesn't.
How much work does the electric field do in moving a -7.7 hC charge from the ground to a point whose potential is +55 V higher?
4. Priya notices thet the pressure inside one of her car tyres is too low. She pumps up the tyre to a higher pressure. a) What happens to the number of particles in the car tyre? b) What happens to the distance between particles as pressure increase? c) One of the tyres gets a puncture(small hole) . What happens to the pressure inside the tyre?
Answer:
a) the number of particles increases
b) average distance between them should decrease
c) the number of particles decreases, the pressure must also decrease
Explanation:
a) When the girl pumps to increase the pressure inside the tire she introduces more particles. Therefore the number of particles increases
b) as the volume of the tire does not change and there are more particles, the average distance between them should decrease
c) When a hole is opened, some of the particles inside the tire come out, so as the number of particles decreases, the pressure must also decrease
The object having uniform velocity has zero acceleration, why?
in an exothermic reaction, chemical energy is converted to ____ energy.
FILL IN THE BLANK.
MECHANICAL OR THERMAL.
Answer:thermal energy
Explanation:
please mark this answer as brainliest
What device increases voltage?
A. generator
B. motor
C. step-down transformer
D. step-up transformer
Your answer would be C.
A step-up transformer is a transformer that raises voltage from main to secondary by having more secondary winding turns than primary winding turns.
Hope this helps; have a great day!
A rock with a mass of 6 grams has greater thermal energy than a rock with a mass of 7 grams. True or false?
Answer:
Explanation:
False
Why are bases of pillars of bridge
made broad?
Answer:
to lower the centre of gravity
Explanation:
what will happen if you increse the amplitude of a drum hit
The sound is perceived as louder if the amplitude increases, and softer if the amplitude decreases. As the amplitude of the sound wave increases, the intensity of the sound increases. Sounds with higher intensities are perceived to be louder.
Define the types of friction and give FOUR examples of each
Static Friction
Rolling Friction
Sliding Friction
Fluid Friction
Answer:
Static Friction - acts on objects when they are resting on a surface
Sliding Friction - friction that acts on objects when they are sliding over a surface
Rolling Friction - friction that acts on objects when they are rolling over a surface
Fluid Friction - friction that acts on objects that are moving through a fluid
Explanation:
Examples of static include papers on a tabletop, towel hanging on a rack, bookmark in a book , car parked on a hill.
Example of sliding include sledding, pushing an object across a surface, rubbing one's hands together, a car sliding on ice.
Examples of rolling include truck tires, ball bearings, bike wheels, and car tires.
Examples of fluid include water pushing against a swimmer's body as they move through it , the movement of your coffee as you stir it with a spoon, sucking water through a straw, submarine moving through water.
list down the different phases of the Moon
Answer:
new Moon.
waxing crescent Moon.
first quarter Moon.
waxing gibbous Moon.
full Moon.
waning gibbous Moon.
last quarter Moon.
waning crescent Moon.
Explanation:
Answer:
NEW MOON
WAXING CRESCENT
FIRST QUARTER
WAXING GIBBOUS
FULL MOON
THIRD QUARTER
WANING GIBBOUS
WANING CRESCENT
Explanation:
HOPE IT HELPS
A 75N horizontal force is sufficient to move a 150N box on a level road at a uniform speed. What is the coefficient of friction between the box and the road?
Answer:
[tex]\mu_k=0.5[/tex]
Explanation:
From the question we are told that:
Force [tex]F=75N[/tex]
Weight [tex]W=150N[/tex]
Generally the equation for coefficient of friction [tex]\mu_k[/tex] is mathematically given by
[tex]\mu_k=\frac{F}{mg}[/tex]
[tex]\mu_k=\frac{75}{150}[/tex]
[tex]\mu_k=0.5[/tex]
What current flows through a 15 ohm fixed resistor when it operates on a 120-volt outlet?
Answer: current is 8.0 A
Explanation: R= U/I I = U/R = 120 V/15 Ω= 8.0 A
A graph here shows the displacement of two walkers over time. Waliper 1 is graphed in red while walker 2 is graphed
in blue. Which statements are supported by the information in the guaph? Select ALL that apply.
)
Α)
Both walkers had the same speed overall.
B)
Walker 2 was at rest for the first five seconds.
C)
Walker 1 moved faster overall than walker 2 by the end.
D)
Walker 2 moved faster overall than walker 1 by the end.
E)
Both walkers had reached the same distance at fifteen seconds.
Answer:
B) Walker 2 was at rest for the first five seconds. D) Walker 2 moved faster overall than walker 1 by the end. E) Both walkers had reached the same distance at fifteen seconds.
Explanation:
I did the UsaTestPrep
What will happen to the size of the Aragorn Sea over time?
What kind of waves can cause the most damage on the earth's surface?
Answer:
Surface waves, in contrast to body waves can only move along the surface. They arrive after the main P and S waves and are confined to the outer layers of the Earth. They cause the most surface destruction. Earthquake surface waves are divided into two different categories: Love and Rayleigh.
Explanation:
Hope this helped Mark BRAINLIEST!!!
Answer:
Surface waves are the seismic waves that cause the most damage.
Explanation:
Given the height of rod,length of shadow of tree and length of shadow of the rod, estimate the height of the tree? Given:height of rod=150cm,Length of shadow of the rod=120cm and length of shadow of the tree =800cm
Answer:
1000 cm.
Explanation:
To obtain the estimated tree height :
(Height of rod / length of rod shadow) = (height of tree / length of tree shadow)
Substituting values into the formula :
(150cm / 120 cm) = (height of tree / 800 cm)
Using cross multiplication :
Height of tree * 120 = 150 * 800
Height of tree = (150 * 800) / 120
Height of tree = 120,000 / 120
Height of tree = 1000
Hence, estimate height of tree = 1000 cm
Which applications, either for diagnostic purposes or for therapeutic purposes, involve the use of X-rays? Check all that apply.
CT scan
MRI
radiography
brachytherapy
laser eye surgery
radioisotope imaging
external beam radiation therapy
fluoroscopy
Answer:
1,3,7,8
Explanation:
Edge 2021
Explain why a person cannot dive in the Mariana Trench in the Pacific Ocean to a depth of approx. 11,000 m without appropriate protective equipment
Answer:
Plzzzz answer fast......
Two harmonic waves moving in the same direction are described by y1(x,t)=10.2sin(4x-700t) and y2(x,t)=10.2sin(4x-700t-7.9). What is the amplitude of the resultant wave at interference
Answer:
14.42 units
Explanation:
The waves are given as follows :
[tex]y_1(x,t)=10.2\sin(4x-700t)\\\\y_2(x,t)=10.2\sin(4x-700t-7.9)[/tex]
We need to find the amplitude of the resultant wave at interference. Let it be A. So,
[tex]A=\sqrt{10.2^2+10.2^2} \\\\=14.42\ units[/tex]
So, the amplitude of the resultant wave is equal to 14.42 units.
What is another term for a pull on an object? O A. Acceleration O B. Speed O c. Force O D. Velocity
Answer:
Acceleration
Explanation:
What is the polarity of each of the earths magnetic poles ? Explain you answer
Answer:
When you put un-like poles together (South facing North) you can feel magnetic attraction. In the Northern Hemisphere, your compass needle points North, but if you think about it for a moment, you will discover that the magnetic pole in the Earth's Northern Hemisphere has to be a South polarity.
A watch costs Rs. 8136 when it is 10% discounted and 13%
VAT is added then find out discount and VAT amount? By
how much percentage VAT amount is more than discount
amount.
Ans: 17%
Explanation:
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