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.
Answer:
Hydrogen has one electron and one proton
Answer: 8.1 x 10^24
Explanation:
I(t) = (0.6 A) e^(-t/6 hr)
I'll leave out units for neatness: I(t) = 0.6e^(-t/6)
If t is in seconds then since 1hr = 3600s: I(t) = 0.6e^(-t/(6 x 3600) ).
For neatness let k = 1/(6x3600) = 4.63x10^-5, then:
I(t) = 0.6e^(-kt)
Providing t is in seconds, total charge Q in coulombs is
Q= ∫ I(t).dt evaluated from t=0 to t=∞.
Q = ∫(0.6e^(-kt)
= (0.6/-k)e^(-kt) evaluated from t=0 to t=∞.
= -(0.6/k)[e^-∞ - e^-0]
= -0.6/k[0 - 1]
= 0.6/k
= 0.6/(4.63x10^-5)
= 12958 C
Since the magnitude of the charge on an electron = 1.6x10⁻¹⁹ C, the number of electrons is 12958/(1.6x10^-19) = 8.1x10^24 to two significant figures.
Answer:
Option B
Explanation:
The phase difference is found by subtracting the 2.3m for the receiver from the other speaker which is 2.9m hence
Phase difference= 2.9-2.3= 0.6
Answer:
The amount of heat required is 
Explanation:
From the question we are told that
The mass of water is 
The temperature of the water before drinking is 
The temperature of the body is 
Generally the amount of heat required to move the water from its former temperature to the body temperature is
Here 
is the specific heat of water with value 
So
=> 
Generally the no of mole of sweat present mass of water is
Here 
is the molar mass of sweat with value
=> 
=> 
Generally the heat required to vaporize the number of moles of the sweat is mathematically represented as
Here 
is the latent heat of vaporization with value 
=> 
=> 
Generally the overall amount of heat energy required is
=> 
=>
