Answer:
h=17m
v=18.6 m/s
Explanation: The question can be solved by applying kinematic equations of motion
Data
u=0
a=g
t=1.9 secs
firstly to calculate the height

to find the final velocity

The acceleration graph is straight line of equation y=9.8 as acceleration is constant:
Velocity graph is given by y=9.8x ( y as velocity and x as time):
Displacement graph is given by y=4.9x^2 ( x as time, y as displacement):
These graphs are only applicable from x=0 to x=1.9 ... ignore the other graph sections

Actually Welcome to the Concept of the Force and Power.
Since, according to the Newton's law,
Force = mass * Acceleration.
hence, here
Force = 142 N, accelration = 22.75 m/s2
hence, mass = 142/22.75
===> Mass = 6.24 Kg
hence the mass of the shot is 6.24 Kg
Answer:
0.0059
Explanation:
According to the question the seismic activity density is given by

Here,
Number of Earthquakes over a given time span = 424
The land area affected = 71300 mi²
So,

The seismic activity density is 0.0059
Explanation:
The position vector r:

The velocity vector v:

The acceleration vector a:



Answer:
Robert Hooke
Was the first to use the word "cell"
Observed cork cells
Anton van Leeuwenhoek
Observed "animalcules"
Used polished lens
.
Explanation:
Anton van Leeuwenhoek is known as father of microbiology. He is credited to improve the quality of lens in microscope. His first observation of organisms called animalcules.
He is credited to have build microscope that could get magnified by 200 times. He used word animalcules for small organisms from pond water when first observed in microscope. He discovered protozoa and named it animalcules".
Robert Hooke is famed for discovering cell from a cork of plant. He observed a compartment or honey comb like divisions when observed these cork cells under the microscope and named it cell. He was only able to see the cell wall as the cork cells are dead cells.