Answer:
force experienced by A and B are equal and opposite, that is total momentum before collision is equal to total momentum after collision if no external forces act on them which proves the principle of conservation of linear momentum.
A boy with a mass of 45 kg runs towards a stationary trolley with a total mass of 30 kg. The boy then jumps on the trolley and the trolley starts to move.
a) Explain why the trolley starts to
move after the boy jumps on it.
b) Calculate the magnitude of the
velocity of the trolley after the boy jumps on it.
anyone here cold helps me to solve and explain the answer... thanks in advance
Answer:
The trolley moves because a force of exertion is pushed onto it when the boy launches himself onto it. It also moves in a direction, so velocity is applied to it.
The velocity goes from stand-still to something. Also, to find velocity, I think acceleration and time are 2 constants that are needed to find velocity, which is not present in the question.
Sorry if this is not the answer you wanted.. I just gave a basic guess as to what I think the answer is. I just started to learn physics.
Explanation:
value of g is independent of
Answer:
mass
Explanation:
The value of g (acceleration due to gravitation) is independent of the mass of the object.
Question 3 A woman sitting in a stationary car notices a man cycling past her at 40 km/hr. Five seconds after he passes her car, she starts following after him. What is the shortest possible distance in which she will catch up to the cyclist if he maintains hrs speep and she obeys the speed limit of 70 km/hr? The car has a maximum acceleration
The shortest possible distance in which she catches up with the man is 129.7 m.
The given parameters:
speed of the man, v₁ = 40 km/hr
speed of the woman, v₂ = 70 km/hr
time when the woman started moving, t₁ = 5 seconds
To find:
the shortest distance when she catches up with the manConvert the given speed in km/h to m/s
3.6 km/h = 1 m/s40 km/h = 40/3.6 = 11.11 m/s70 km/h = 70/3.6 = 19.44 m/sCalculate the distance moved by the man before she started following him.
Distance moved by the man = speed x time
= 11.11 m/s x 5 s
= 55.55 m
Let the time the woman catches up with the man = t
Apply the following simple principle to calculate the time.
The man is moving forward and the woman is moving forward to close the gap between them, thus both speeds are working against each other.
[tex](v_2-v_1)t = 55.55 \ m[/tex]
the difference in the speed is because they are working against each other.[tex](19.44 - 11.11)t = 55.55\\\\8.33t = 55.55\\\\t = \frac{55.55}{8.33} \\\\t = 6.67 \ s[/tex]
The time when the woman catches up with the man = 6.67 s
The shortest distance at which the woman catches up with the man is calculated as;
Shortest distance = woman's speed x time when she catches up
= 19.44 m/s x 6.67 s
= 129.7 m
Thus, the shortest possible distance in which she catches up with the man is 129.7 m.
Learn more here: https://brainly.in/question/9541933?tbs_match=3
A positively charged glass rod is bought close to a suspended metal needle. What
can we say about the charge on the needle given that the needle is
a) attracted ?
b) repelled ?
Answer:
attracted
Explanation:
opposite charges attract each other when the rub against each other
Answer:
This depends because the electrostatic force obeys the principle that states that force between both of the particles does not get affected by the charges of the other thus if the needle is getting attracted it possess negative charges( the opposite charge) .And if they repel it means they have the same charges ( positive charges).
Jo, Daniel and Helen are pulling a metal ring. Jo pulls with a force of 100N in one direction and Daniel with a force of 140N in the opposite direction. If the ring does not move, what force does Helen exert if she pulls the same direction as jo?
Answer:
she is pulling with 40 N force
Explanation:
The ring does not move means that the forces are equal.
Let's call Jo's force x
We have the quation
140 = x + 100
x = 40
Aristotle said that if you dropped a large object and a smaller object that the larger
object would hit the ground first.
We now know that that is___
not true.
true
Answer: not true
Explanation: mass < weight
A:10i - 2j -4k and B: i +7j - k. Determine |A-B|
A - B = (10i - 2j - 4k) - (i + 7j - k)
A - B = 9i - 9j - 3k
|A - B| = √(9² + (-9)² + (-3)²) = √189 = 3√19
what is annual average inflation
What is the field outside the capacitor plates in a parallel capacitor?
Answer is zero
Plz mark me brainlist
Explanation:
Outside two infinite parallel plates with opposite charge the electric field is zero, and that can be proved with Gauss's law using any possible Gaussian surface imaginable
the weight of a girl is 400N .the area of each shoe with which she is standing is 40cm square . calculate the pressure exerted by her both feet?
Answer:
P=2*[tex]10^{5}[/tex]Pa
Explanation:
P=P1+P2
P1=[tex]\frac{F}{A}[/tex]
Putting the values
P1=[tex]\frac{400}{40*10^{-4} }[/tex]
P1=1*[tex]10^{5}[/tex]
It is the pressure exerted by 1 feet
Pressure exerted by 2nd feet is also equal to the pressure exerted by 1st feet then
P2=1*[tex]10^{5}[/tex]
P=P1+P2
P=(1*[tex]10^{5}[/tex])+(1*[tex]10^{5}[/tex])
P=200000PaP=2*[tex]10^{5}[/tex] Pa
Do black holes really exist?
Yes, black holes 100% exist. They suck everything in their paths through a process known as spaghettification.
When a piece of metal mass of 72.17 g is
dropped into a graduated cylinder containing
20.92 mL of water, the water level rises to
26.64 mL. What is the density of the metal?
Answer in units of g/cm3
.
Answer:
Explanation:
The trick is in finding the volume.
Final Volume = 26.64
Initial Volume=20.92 Subtract
Metal Volume 5.72 cm^3
Density = mass / volume
Density = 72.17 / 5.72
Density = 12.617
What is crowbar? Class 8
Answer:
Crowbar is a tool made of metal rods that are flattened at both ends, with one of them curved. There is also a crowbar that is curved at both ends.
hope it helped
why is it important for heat sinks to be made of metal and have a large surface area?
Which two particles are present in the nucleus of an atom? Electrons and neutrons Electrons and molecules 1 TH O Protons and neutrons O Protons and electrons
Answer:
Protons and neutrons
Explanation:
If A finishes a work in less time than B,who has more power explain why
if your average speed is 3 m/s, how far have you traveled in 1 second, 2 second, 3 seconds?
Answer:
in 1 second 3m, in 2 seconds 6m, in 3 seconds 9m.
Explanation:
distance=speed × time
the value of mass of a body is everywhere
Explanation:
The value of mass of a body is not same everywhere.
Because it depends on gravity and the gravity isn't same at every places.
Answer:
Mass is the quantity of matter contained in a body, while weight is the force by which the body is pulled to the earth's center. Mass is an intrinsic property of a body, as it remains the same everywhere in the universe. Weight is variable due to change in the magnitude of the gravitational force applied by the earth.
which type of bonds can carbon atoms form with other carbon Atoms
Explanation:
A carbon atom can form covalent bonds with other carbon atoms
What is the average velocity of the particle from rest to 9 seconds?
OA.
1 meter/second
OB.
2 meters/second
OC.
3 meters/second
OD.
4 meters/second
Answer:
B 2m\s
Explanation:
18 m of displacement over the course of 9 seconds
18/9 = 2 m\s
What are two benefits of scientists using a diagram to model the water cycle?
A. It can show changes that occur in many different parts of Earth at
the same time.
B. It can be used to show how the parts of the cycle relate to one
another.
C. It can be used to show as much detail as is present in the actual
water cycle.
OD. Only a few factors in the water cycle can be shown on the
diagram.
Explanation:
it can be used to show how the parts of the cycle relate to one another
what change occurs to the gravitational force of attraction between two bodies when the distance between them is made half 1 by 2 by keeping masses constant
Explanation:
Since the gravitational force is inversely proportional to the square of distance, changing the distance to half the original results in 4 times the original force
explain fundamental quantities in
physics
Answer:
fundamental quanties are mass , time, length, temperature , amount of substance and luminous intensity. All other physical quantity are derived quantity and be made from fundamental quanties.
Explanation:
hope it helps u
Answer:
The other person answered
Explanation:
which is a symbol that represents SI units for temperature?
A. °C
B. g
C. L
D. °F
Answer:
A. °C
Explanation:
[tex]{ \sf{degree \: celcius}}[/tex]
Answer:
Symbol k represent SI UNITS
Explanation:
□: the action of an object spinning around on its □
Answer:
head gyxicjcurgcugxgox6r
Who among the old Greek Philosophers/Scientists was the first to systematically study the
Stars?
Previous Answer:
Aristotle
Change:
Aristarchus
Answer:
Aristarchus of Samos was the first Greek philosopher to believe the solar system was organized around the Sun, rather than the Earth. The heliocentric was very unpopular during Aristarchus' lifetime, although it would inspire astronomers centuries later. Ptolemy was an astronomer and mathematician.
What is term for the group of phenomena that includes, melting, boiling, freezing, and condensation?
Phase Change
Seasonal Change
State Change
Time Change
Consider the mass-on-a-spring system as shown in the figure below. The spring has a spring constant of 1.81e+3 N/m, and the block has a mass of 0.988 kg. There is a constant force of kinetic friction between the mass and the floor of 1.79 N. Starting with the spring compressed by 0.172 m from its equilibrium position, how far will the block travel once it leaves the spring? (Assume that block leaves the spring at at the spring's equilibrium position, marked x=0 in the figure.
K1Answer:
s= 6.5cm
Explanation:
Point 1: just right before the block leaves the spring
Point 2: the block has v2=0 (stops moving)
Apply Kinetic-Work Theorem:
K1 + U1 + Wother = K2 + U2
K1=0
U1= 1/2×k×x² (k= 1.81e+3 N/m and x= -0.172 m)
Wother = F×s= 1.79×s
K2=0
U2=0
=> s= 6.5cm
This is my attempt to solve. Let me know if this isn't right
Explain the term majority and minority carriers of a material with respect to the acceptor and donor impurity.
Answer:
carriers and so are called majority carriers. A few thermally generated electrons will also exist in the p side; these are termed minority carriers. On the n side the electrons are the majority carriers, while the holes are the minority carriers. Near the junction is a region having no free-charge…
Answer:
The majority charge carriers carry most of the electric charge or electric current in the semiconductor. Hence, majority charge carriers are mainly responsible for electric current flow in the semiconductor. The charge carriers that are present in small quantity are called minority
A rocket of mass 40,000kg propelled by a force 10⁶N acquires a speed of 3000m/s. determine the power extended
Answer:
3×10⁹ W
Explanation:
Power = work / time
Power = force × distance / time
Power = force × velocity
P = Fv
P = (10⁶ N) (3000 m/s)
P = 3×10⁹ W