Answer:
if the tempertaure is increase it effects us very badly. it affects not only us . it effects our whole enviroment.
4) Choose Yes or No next to the descriptions to indicate whether or not an object
is accelerating,
A car slows down,
A car stays the same speed,
A car goes faster,
Luke walks at a constant speed of 4 mph,
Luke walks north at a constant speed of 4 mph,
Luke walks north at a constant speed of 4 mph, turns right, and walks
Type here to search
A block is released from rest at the top of a hill of height h. If there is negligible friction between the block and the hill, the block arrives at the bottom of the hill with speed v.
Answer:
v / √2
Explanation:
A blocked from rest at the top of a hill of height h it there is negligible friction between the block and the hill, the block arrives at the bottom of the hill with speed. The block is released from rest at the top of another hill with a rough surface and height h. if one-half of the initial mechanical energy of the block Earth System is lost due to friction as the block descends the hill, the block will reach the bottom of the hill with a speed of?
Solution:
For the first block block, its potential energy at the top of the hill when it is at rest is converted to kinetic energy after release with a velocity v.
The kinetic energy = (1/2)mv², where m is the mass of the block.
For the other block placed on the top of the rough hill, the mechanical energy (kinetic energy) is halved due to the roughness of the hill. If u is the speed of this block at the bottom of the hill then:
kinetic energy of block on the rough hill = (1//2)mu²
Hence:
(1//2)mu² = half of main system kinetic energy
(1//2)mu² = 1/2 * (1/2)mv²
mu² = (1/2)mv²
u² = (1/2)v²
u = √(v²/2)
u = v / √2
Hence the speed at the bottom of the rock of the block placed on the rough surface is v / √2
Rodney hits a 0.060 kg tennis ball straight up with a speed of 15 m/s from a height of 2.2 m above the ground. How fast is the ball going when it is 9.5 m above the ground?
Answer:
Explanation:
From the question we are told that
The mass of the tennis ball is [tex]m = 0.060 \ kg[/tex]
The speed is [tex]u = 15 \ m/s[/tex]
The initial height of the ball is [tex]h_o = 2.2 \ m[/tex]
The height considered is [tex]h = 9.5 \ m[/tex]
Generally the time taken to reach the considered height is mathematically evaluated from the equation of motion as follows
[tex]h = h_o + ut - \frac{1}{2} gt^2[/tex]
=> [tex]9.5 = 2.2 + 15t - \frac{1}{2} * 9.8 t^2[/tex]
=> [tex]7.3 = 15t - 4.9t^2[/tex]
=> [tex]4.9t^2 -15t + 7.3[/tex]
solving the above equation using quadratic formula
[tex]t= 0.6070 \ s[/tex] and [tex]t_1 = 2.454 \ s[/tex]
Generally from kinematic equation we have that
[tex]v = u - gt[/tex]
=> [tex]v= 15 - 9.8 * 0.6070[/tex]
=> [tex]v= 9.0514 \ m/s[/tex]
Note if we had used the second values of time the velocity at 9.5 \ m would have been negative which is not correct given that at maximum height velocity is zero
3 Kyra and Pari are timing how long it takes for 1 g of sugar to dissolve in hot water.
Kyra records a time of 24.3 seconds. Pari records a time of 24 seconds. Whose reading
is more precise? Why?
Answer:
Kyra is more precise.
Explanation:
Kyra is more precise as she has included the exact point second it had dissolved whereas Pari just rounded it to the closest number making her write a whole number that was rounded down.
In the experiment shown below, which is greater, the force of gravity on the pith balls (Fg) or the electrostatic force between them (Fq)?
Fg > Fq
Fg = Fq
Fg < Fq
Not enough information is given.
Answer: Fg < Fq
Explanation: just took the lab test edge 2020
The electromagnetic force is greater than the gravitational force option third Fg < Fq is correct.
What is the electrostatic force?It is a force imposed by one charge on another as a result of the field. The electrostatic force produced by one line charge on another line charge separated by r is determined by the charge potency of each charge as well as the separation distance between them.
Force of gravity is given by:
[tex]\rm F_g=\dfrac{Gm_1m_2}{r^2}[/tex]
The electrostatic force is given by:
[tex]\rm F_q = \dfrac{kq_1q_2}{r^2}[/tex]
On the atomic scale, electrons, for example, have very little mass but a very large charge. As a result, electromagnetic forces rule.
Thus, the electromagnetic force is greater than the gravitational force option third Fg < Fq is correct.
Learn more about the electrostatic force here:
https://brainly.com/question/9774180
#SPJ2
define steam distillation
Answer:
Steam distillation is a separation process which consists in distilling water together with other volatile and non-volatile components.
The force of gravity is
_m/s2
The force of gravity is positive 9.8m/s^2.
fill in the blanks
a. Work is assosiated with ___________ and _________ .
Answer: Job and career
Explanation:
Work is associated with job and career. If somebody is having a great career and if somebody wants a great career he will look for a job that is fitting his career and in that way, he will work for it to have an even better career which will bring him a better job.
the specific heat of gold is 0.031 calories degrees Celsius and the specific heat of silver is 0.057 calories degrees Celsius so if equal. amounts of each metal are exposed to equal heating which will heat up faster
Answer:
Explanation:
Given:
Specific heat of gold = 0.031cal/°C
Specific heat of silver = 0.057cal/°C
To know the metals that will heat up faster, we must understand the meaning of specific heat capacity.
It is the amount of heat required to raise the temperature of 1g of a substance by 1°C.
Now,
The higher the specific heat capacity the more energy it is required to heat up the substance.
So, Gold with a specific heat capacity of 0.031cal/°C will heat up faster.
A 2.0-kg block starts from rest on the positive x axis 3.0 m from the origin and thereafter has an acceleration given by in m/s2. At the end of 2.0 s its angular momentum about the origin is:
Answer:
hello your question is incomplete below is the complete question
A 2.0 kg block starts from rest on a positive x axis 3.0m from the origin and thereafter has an acceleration given by a= 4.0i - 3.0jin m/s2. At the end of 2.0 s, its angular momentum about the origin is ______.
answer : L = ( 2 kg ) [(-18m^2/s)k]
Explanation:
velocity vector(v) = (4.0i - 3.0j )(2.0s)
position vector(r) = ( 3.0m)i
determine the angular momentum about the origin
L = m ( r * v )
attached below is the detailed solution
Answer:
Angular momentum about the origin = [tex](-36kg.rad/s)k[/tex]Explanation:
Given the acceleration,
[tex]v(t) = 4ti - 3tj[/tex]
So,
[tex]v(2) = 8i - 6j[/tex]
similarly,
[tex]x(t) = (3 + 2t^2) i - 1.5t^2 j[/tex]
so,
[tex]x(2) = 11i - 6j[/tex]
Angular momentum,
[tex]=mx(2)*v(2)\\\\=2*((-6x0-0x-6)i +(0x8-11x0)j +(11x-6--6x8)k)\\\\=2*(0i +0j -18k)\\\\=(-36kg.rad/s)k[/tex]
For more information on angular momentum, visit
https://brainly.com/subject/physics
what polarity must the red tip of the compass needle be since it points toward the south pole of the magnet?
Answer: positive
Explanation: because opposites attract and north=positive and south=negative the answer should be positive.
The polarity of the red tip of the compass needle must be at the north of the earth, since it points toward the south pole of the magnet.
What is meant by polarity of a magnet ?Polarity of a magnet is defined as the orientation of both the north and south poles of the magnet in space.
Here,
We know that, the opposite poles attract.
The magnetic needle is arranged in a such a way that, the red tip of the magnetic compass needle is actually pointing towards the geographic north pole of the earth.
In order to point the compass needle towards the magnetic south pole, the south pole of the magnet must be located in the geographic north pole.
Hence,
The polarity of the red tip of the compass needle must be at the north of the earth, since it points toward the south pole of the magnet.
To learn more about polarity of magnet, click:
https://brainly.com/question/15329793
#SPJ2
A 0.17 kg ball of dough is thrown straight up into the air with an initial speed of 12 m/s. The acceleration of gravity is 9.81 m/s 2 . a) What is its momentum at its maximum height? Answer in units of kg · m/s
Answer:
The momentum of the ball at the maximum height is zero (0 kg.m/s).
Explanation:
Given;
mass of the ball, m = 0.17 kg
initial velocity of the ball, u = 12 m/s
acceleration due to gravity, g = 9.81 m/s²
At maximum height the final velocity of the ball, v = 0
Momentum of the ball at the maximum height is given as;
P = mv
P = (0.17)(0)
P = 0 kg.m/s
Therefore, the momentum of the ball at the maximum height is zero (0).
what is relative density?
Study the distance-time graph, showing the distances that eight different things cover in 120 seconds or less. The letters below correspond to the lines on the graph. For each object, calculate the average speed, and then match it with the closest correct answer.
A:
B:
C:
D:
E:
F:
G:
H:
Answer:
This question appear incomplete
Explanation:
This question appear incomplete because there is no list of closest correct answer there. Although can still be well attempted.
The formula to be used here is
average speed = distance ÷ time
The unit of speed here would be meters per second (m/s). However, some of the lines do not really fall on a measurable line on the graph and can only be "best assumed".
A: distance is 1600 meters
time appear to be 4 seconds (definitely less than 5 seconds according to the graph).
speed = 1600 ÷ 4
speed = 400 m/s
B: distance is 1600 meters
time appear to be 18 seconds (definitely less than 20 seconds according to the graph)
speed = 1600 ÷ 18
speed = 88.89 m/s
C: distance is 1600 meters
time is 65 seconds
speed = 1600 ÷ 65
speed = 24.62 m/s
D: distance is 1600 meters
time is 105 seconds
speed = 1600 ÷ 105
speed = 15.24 m/s
E: distance is 1100 meters
time is 120 seconds
speed = 1100 ÷ 120
speed = 9.17 m/s
F: distance is 500 meters
time is 120 seconds
speed = 500 ÷ 120
speed = 4.17 m/s
G: distance appear to be 250 meters
time is 120 seconds
speed = 250 ÷ 120
speed = 2.08 m/s
H: distance appear to be 50 meters
time is 120 seconds
speed = 50 ÷ 120
speed = 0.42 m/s
The average speed for each object are:
1. The average speed of A is 400 m/s
2. The average speed of B is 88.89 m/s
3. The average speed of C is 24.62 m/s
4. The average speed of D is 15.24 m/s
5. The average speed of E is 9.17 m/s
6. The average speed of F is 4.17 m/s
7. The average speed of G is 2.08 m/s
8. The average speed of H is 0.33 m/s
Average speed is defined as the total distance travelled divided by the total time taken to cover the distance.
Average speed = Total distance / total timeWith the above formula, we can obtain the average speed for each object as follow:
1. Determination of average speed of A
Total distance = 1600
Total time = 4 s
Average speed =?Average speed = 1600 / 4
Average speed of A = 400 m/s2. Determination of average speed of B
Total distance = 1600
Total time = 18 s
Average speed =?Average speed = 1600 / 18
Average speed of B = 88.89 m/s3. Determination of average speed of C
Total distance = 1600
Total time = 65 s
Average speed =?Average speed = 1600 / 65
Average speed of C = 24.62 m/s4. Determination of average speed of D
Total distance = 1600
Total time = 105 s
Average speed =?Average speed = 1600 / 105
Average speed of D = 15.24 m/s5. Determination of average speed of E
Total distance = 1100
Total time = 120 s
Average speed =?Average speed = 1100 / 120
Average speed of E = 9.17 m/s6. Determination of average speed of F
Total distance = 500
Total time = 120 s
Average speed =?Average speed = 500 / 120
Average speed of F = 4.17 m/s7. Determination of average speed of G
Total distance = 250
Total time = 120 s
Average speed =?Average speed = 250 / 120
Average speed of G = 2.08 m/s8. Determination of average speed of H
Total distance = 40
Total time = 120 s
Average speed =?Average speed = 40 / 120
Average speed of H = 0.33 m/sLearn more: https://brainly.com/question/14988345