Given:
m(mass of the box)=10 Kg
t(time of impact)=4 sec
u(initial velocity)=0.(as the body is initially at rest).
v(final velocity)=25m/s
Now we know that
v=u+at
Where v is the final velocity
u is the initial velocity
a is the acceleration acting on the body
t is the time of impact
Substituting these values we get
25=0+a x 4
4a=25
a=6.25m/s^2
Now we also know that
F=mxa
F=10 x6.25
F=62.5N
Answer: The correct option is option E (the Sun is seen blocking different constellations in the course of a year.
Explanation:
The earth, which is one of the planets of the solar system that supports life, is shperical in shape. The spherical ( round) shape of the earth is marked by the intervening highlands and oceans on its surface.
Evidence to show that the earth is shperical are:
--> The Lunar eclipse: During an eclipse of the Moon, the shadow of the Earth is always seen to be round.
--> Ships Visibility: When ships travel a large distance away, we see their hulls disappear first and their masts disappear last.
-->Altitude of Polaris (North Star): The height of the North Star changes as we travel to different latitudes. That is ,increases as you move toward the North pole, or decreases as you move toward the equator.
--> Aerial photographs: Photographs of the Earth from space always show a round body.
The statement that doesn't prove that the earth is spherical in shape is (the Sun is seen blocking different constellations in the course of a year). The sun is seen in front of stars blocking different constellation in a year because the earth orbits round the sun in a year and not that it is shperical in shape.
Answer:
Force is repulsive hence direction of force is away from wire
Explanation:
The first thing will be to draw a figure showing the condition,
Lets takeI attractive force as +ve and repulsive force as - ve and thereafter calculating net force on outer left wire due to other wires, net force comes out to be - ve which tells us that force is repulsive, hence direction of force is away from wire as shown in figure in the attachment.
Answer:
When both initial speed and initial displacement is doubled then amplitude will be doubled.
Explanation:
Given that :- Amplitude of simple harmonic Oscillator is doubled.
So,
Formula of Simple harmonic oscillator is ...........(1)
Where X = Position in (m,cm,km.....)
A = Amplitude in (m,cm,km.....)
F = Frequency in (Hz)
T = Time in (sec.)
Ф = Phase in (rad)
For initial displacement taking t=0 we get,
Initial displacement = .................(2)
Now taking equation (1) and differentiating it w.r.t to (t) we get
taking t=0 for initial speed then we get,
Initial speed = ...............(3)
observing equation (2) & (3) that the initial displacement and initial speed depends on the Amplitude of the Oscillator.
Hence,
when both initial speed and displacement is doubled then amplitude will be doubled.
To solve this problem we will use the linear motion kinematic equations, for which the change of speed squared with the acceleration and the change of position. The acceleration in this case will be the same given by gravity, so our values would be given as,
Through the aforementioned formula we will have to
The particulate part of the rest, so the final speed would be
Now from Newton's second law we know that
Here,
m = mass
a = acceleration, which can also be written as a function of velocity and time, then
Replacing we have that,
Therefore the force that the water exert on the man is 1386.62