Until there's none of it left. Different radioactive isotopes decay at different rates. And a bigger pile of it will last longer than a smaller pile. Without knowing WHICH radioactive isotope you're asking about, and how much of it you started out with, the answer could turn out to be anywhere between 1 millionth of a second and 1 million years.
Light rays travel along _____ paths. A. curved B. straight C. changing D. unpredictable
Answer: Straight :)
Explanation:
LIght rays travel in straight paths and it is impossible for them to travel in curved, unpredictable, and changing paths
bumper car A (281 kg) moving +2.82 m/s makes an elastic collision with bumper car B (209 kg) moving +1.72 m/s what is the velocity of car A after the collision (unit = m/s) remember: right is (+), left is (-)
Answer: V1 = 3.559 - 0.744V2
Explanation: Given that the
bumper car A has
Mass M1 = (281 kg) moving with
Velocity U1 = 2.82 m/s
bumper car B has
Mass M2 = (209 kg) moving with
Velocity U2 = 1.72 m/s
Where U1, U2 are the initial velocity of the two cars
Since the collision is elastic, we will use the formula below,
M1U1 + M2U2 = M1V1 + M2V2
Substitute the values into the formula
281×2.28 + 209×1.72 = 281V1 + 209V2
640.68 + 359.48 = 281V1 + 209V2
1000.16 = 281V1 + 209V2
Make V1 the subject of formula
281V1 = 1000.16 - 209V2
V1 = 1000.16/281 - 209V2/281
V1 = 3.559 - 0.744V2
Therefore, the velocity of car A which
is V1 after the collision will be expressed as V1 = 3.559 - 0.744V2
Which best describes the act of using senses or tools to gather information?
ОООО
creating a hypothesis
making an observation
summarizing the results
recording the measurements
Answer:
Making an observation
Explanation:
By observing, you can draw qualitative and quantitative data from the subject of observation
Which of the following data sets has a range of 40? a. {40, 10, 20, 100} c. {40, 10, 20, 50} b. {40, 10, 20, 80} d. {40, 10, 20, 40}
Answer:
C
Explanation:
To answer this problem, we must identify what range is. Range is the difference between the smallest and largest numbers in a set of data. Remember it can be helpful to order your sets of numbers from least to greatest to help you, but it is not mandatory.
Lets take this information for the data sets provided.
For Set A: 100 - 10 = 90, so this won't work.
For Set C: 50 - 10 = 40, this will work.
We know that set c works, so there is no need to move further.
The answer is letter c
What happens when tectonic plates move away from each other? Molten matter cools and sinks towards the core. Lava travels away from the crust and forms the mantle. Molten matter seeps through the crust and forms new land. Lava seeps into the ground through the cracks in the ground.
A car has a speed of 2 m/s and a mass of 1500 kg. What is the cars kinetic energy?
A. 4500 J
B. 3000 J
C. 1500 J
D. 6000 J
Answer:
B
Explanation:
E = mv² / 2
E = (1500kg)(2 m/s)² / 2
E = 6000 J / 2
E = 3000 J
Answer:
B
Explanation: The answer is B because the defining equation for kinetic energy is E=mv^2 / 2
e = (1500kg)(2 m/s)^2 / 2
e = 6000 J / 2
e = 3000 J = 3000 Joules
A person is pulled to the right on a sled (total mass of 52.9 kg) across the surface of a frozen pond with a force of 67.7 Newtons so that they move with a constant velocity. What is the force of friction acting on the sled?
Answer:
67.7 N
Explanation:
Draw a free body diagram of the person on the sled. There are four forces:
67.7 N to the right,
friction force to the left,
weight force down,
and normal force up.
Constant velocity means 0 acceleration.
Sum of the forces in the x direction:
∑F = ma
67.7 N − F = 0
F = 67.7 N
why do you think the moon appears to change shape as it revolves around the earth?
Which converts mechanical energy to electrical energy?
A. A flashlight
B. An electric motor
C. A generator
D. An electromagnet
Answer:
c. A Generator
Explanation:
The whole point of a generator is to produce electrical energy. The generator will use a mechanical motor usually running off of gas to produce electricity.
Jack travelled 360 km at an average speed of 80 km/h. Elaine
took 1.5 hours more to complete the same amount of distance.
What was Elaine's average speed for the whole journey?
km/h
Answer:
Average speed of Elain = 60 km/h
Explanation:
Total Distance covered by Jack = 360km
Average Speed of Jack = 80 km/h
Time taken by Jack to complete his journey = Distance / Average speed = 360 km / 80 km/h
Time taken by Jack to complete his journey = 4.5 hours
As it is given the both Jack and Elain travelled the same amount of distance:
Total distance travelled by Elain = 360 km
It is given that Elain took 1.5 hourse more than Jack to cover the distance, so Time taken by Elain to cover the distance is = 4.5 hours + 1.5 hours = 6 hours
Average speed of Elain = Distance/ time = 360 km / 6 hours
Average speed of Elain = 60 km/h
give one reason why the energy carries bu sound waves decreases as those sound waves travel through air
What are pollutants of greatest concern and who is at risk?
List the 2 advantages and 2 disadvantages of wind as a source of electricity.
Answer:
The first 2 advantages of wind a source of electricity is that it provides you wifi and wind. 2 disadvantages of wind as a source of electricity is that to much wind could knock it down or slow down the source of the electricity.
Explanation:
I know this because i read a article on it.
Can someone help me??
A car travels 1026 km in 6 hours. Find its average speed.
Answer:
171
Explanation:
To work out average speed, you have to do distance divide by time.
1026 divide by 6= 171
I hope that helped you.
The single invention of the ______ has advanced what we know about the universe more than any other scientific technology. a. Sundial b. Calculator c. Telescope d. Calculator
Answer: C
Telescope
Explanation: A telescope is an optical device in which scientists ( astronomers) use to view far away distance objects in the universe.
The single invention of the telescope has advanced what we know about the universe more than any other scientific technology. Because with the use of telescope alone, astronomers could view and study many heavenly objects or bodies and many planets in the universe.
The optical instrument makes very far distant objects appear magnified by using an arrangement of lenses or curved mirrors and lenses for clearer viewing of heavenly objects and planets in our universe.
Land masses that move on Earth are called: a. Continents b. Tectonic continents c. Tectonic plates d. Rock Masses HELP
Answer:
c. tectonic plates
Explanation:
Answer:
the answer is rock masses
2. How far does a car travel in 90 seconds if it is traveling at a speed of 55 m/s?
Answer:
distance = speed × time
= 55m/s × 90s
= 4950 m
if san andreas fault slips 2.5 cm each year how far would it separate in 100 years
Answer:
250cm or 2.5m
Explanation:
using direct variation
the length is = l
the time (year) = t
let k be the constant
so he have:
l=kt
2.5=k× 1
k= 2.5
Now in the next statement the 100 is given but not the length so
l=kt
~ l=k× 100 years
But k = 2.5
so :
l= 2.5×100
l= 250 cm
Hence it will be 250cm or 2.5m at which they will get separated
What happens during a chemical reaction ?
To calculate the density of an object, which of the following values do you
need to know?
A. Volume
B. Buoyancy
C. Weight
D. Mass
Answer:
Volume I think
Explanation:
Answer:
A. volume and D. mass
Explanation:
Density is the amount of matter (mass) in a given space (volume).
The density of an object can be found using the following formula:
d=m/v
where m is the mass and v is the volume.
In order to find the density, you must know the mass and the volume of the object.
Therefore, the correct answers are A. volume and D. mass.
when I jump and land on the surface I exerts a force on the surface and the surface should exert the same amount of force on me, therefore I should be jumping again according to the 3rd law of motion but I don't why is that
You lose energy when you collide with the surface in sound and heat.
It is also that when you jump on the floor, in order to keep you from going through the floor, the floor needs to put a force that will say 'Hey you can't go through me' that's why we build houses and supports with extra strength to hold us, and all the forces we exert on them.
hope this helps
Can someone help??
The maximum acceleration of a fist in a karate punch is 4200 m/s2. The mass of the
fist is 0.60 kg. If the fist hits a wooden block, what force does the wood place on the
fist?
Answer:
F = 2520 N
Explanation:
We have,
The maximum acceleration of a fist in a karate punch is 4200 m/s². The mass of the fist is 0.6 kg.
It is required to find the force that the wood place on the fist. Force is given by the product of mass and its acceleration such that,
F = ma
[tex]F=0.6\times 4200\\\\F=2520\ N[/tex]
So, the force of 2520 N is acting on the wood.
The strong nuclear force is ?
Answer: Option B
Explanation:
The nuclear force is the strongest force in the universe. It is much more stronger than all the other forces and is 100 times stronger than the electric force.
The nuclear forces can be defined as the forces generated due to electron and protons in which the electrons have negative charge on it and the protons have positive charge on it.
Due to this force all the atoms and molecules, elements and compounds are held together.
what is the numerical value in meters per second squared of the acceleration of an object experiencing true free fall
Answer:
9.8m/s²
Explanation:
An object experiening a free fall is simply under the influence of gravity.
When an object is influenced by gravity, the object falls with an acceleration known as acceleration due to gravity.
This acceleration known as acceleration due to gravity has a constant value of 9.8m/s².
How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can
pass a puck as quickly as possible?
OSmooth ice reduces the inertia of the hockey puck.
Smooth ice increases the force used to accelerate the hockey puck.
Smooth ice reduces the unbalanced forces that would slow the hockey puck.
Smooth ice decreases the reaction force that the ice exerts on the hockey puck.
Save and Fxit
Answer:
c
Explanation:
edge 2021
charges can be separated in an isolated system
express the following in metres (1) 52fm (2) 26 Mm (3)12am (4) 69 pm (5) 85 mm
Answer:
1 - 52x10^-15 m
2 - 12x10^-18 m
3 - 26x10^-3 m
4 - 69x10^-12 m
5 - 0.085 meters
Explanation:
Which statement best compares the accelerations of two objects in free fall?
O The heavier object has a greater acceleration.
O The object that has the greater surface area has the lower acceleration,
The object that has the smaller mass has the greater acceleration.
O The objects have the same acceleration
Answer:
C. The object that has the smaller mass has the greater acceleration.
Explanation:
Two objects in free fall are accelerated due to gravity.
According to Newton's second law, if two objects with different masses have same force, then object with light or smaller weight will fall with greater acceleration while the object with greater mass will fall with less acceleration.
Hence, the correct option is C.
Answer:
c
Explanation:
its c
Which letter on the diagram below represents the retina of the eye? A) A B) B C) C D) D
Answer:
THE ANSWER IS OPTION C.
Calculating the Volume of a Cone
Try it
Calculate the volume of the cone.
What is the volume of a cone with a height of 27 cm
and a radius of 13 cm? Round your answer to the
nearest tenth.
VE
cm)
27 cm
113 cm
Answer:
4778.4 cm³
Explanation: