Answer:
The correct answer is a
Explanation:
At projectile launch speeds are
X axis vₓ = v₀ = cte
Y axis 
= v_{oy} –gt
The moment is defined as
p = mv
For the x axis
pₓ = mvₓ = m v₀ₓ
As the speed is constant the moment is constant
For the y axis
p_{y} = m v_{y} = m (v_{oy} –gt) = m v_{oy} - m (gt)
Speed changes over time, so the moment also changes over time
Let's examine the answer
i True
ii False. The moment changes with time
The correct answer is a
Do swimming which make Newtons Third Law
Answer:
2.92 m
Explanation:
As we know, frequency × Wavelength = Speed of light
so here frequency of 102.7 MHz can be written as 102.7× 10⁶ Hz..
So Lambda (wavelength) = 3×10⁸/ 102.7 × 10⁶ which gives 2.92 metres or 2.92 × 10¹⁰ Å
Answer:
The correct answer is the third option: The kinetic energy of the water molecules decreases.
Explanation:
Temperature is, in depth, a statistical value; kind of an average of the particles movement in any physical system (such as a glass filled with water). Kinetic energy, for sure, is the energy resulting from movement (technically depending on mass and velocity of a system; in other words, the faster something moves, the greater its kinetic energy.
Since temperature is related to the total average random movement in a system, and so is the kinetic energy (related to movement through velocity), as the thermometer measures <u>less temperature</u>, that would mean that the particles (in this case: water particles) are <u>moving slowly</u>, so that: the slower something moves, the lower its kinetic energy.
<u>In summary:</u> temperature tells about how fast are moving and colliding the particles within a system, and since it is <em>directly proportional</em> to the amount of movement, it can be related (also <em>directly proportional</em>) to the kinectic energy.
Answer:
Average velocity v = 21.18 m/s
Average acceleration a = 2 m/s^2
Explanation:
Average speed equals the total distance travelled divided by the total time taken.
Average speed v = ∆x/∆t = (x2-x1)/(t2-t1)
Average acceleration equals the change in velocity divided by change in time.
Average acceleration a = ∆v/∆t = (v2-v1)/(t2-t1)
Where;
v1 and v2 are velocities at time t1 and t2 respectively.
And x1 and x2 are positions at time t1 and t2 respectively.
Given;
t1 = 3.0s
t2 = 20.0s
v1 = 11 m/s
v2 = 45 m/s
x1 = 25 m
x2 = 385 m
Substituting the values;
Average speed v = ∆x/∆t = (x2-x1)/(t2-t1)
v = (385-25)/(20-3)
v = 21.18 m/s
Average acceleration a = ∆v/∆t = (v2-v1)/(t2-t1)
a = (45-11)/(20-3)
a = 2 m/s^2
