<span>The scientist thought that the
atom was the smallest particle in the universe is John Dalton. The answer is
letter B. He established the atomic theory which consists of five; elements are
made of extremely small particles called atoms, atoms of different element have
different sizes, mass and physic – chemical properties, atoms cannot be divided
further, destroyed or created, atoms can combine to form compounds and in
chemical reaction, atoms can be combined, separated or rearranged. J.J.
Thompson discovered the electrons in the atom. Ernest Rutherford discovered the
half – life of an atom and Neils Bohr explain the quantum mechanics.</span>
Answer:
positive reinforcer; negative reinforcer
Explanation:
positive reinforcer; negative reinforcer
Receiving delicious food can be seen as a positive reinforcer while escaping electric shock can be seen as a negative reinforcer.
Answer:
The dilation of time.
The falling of objects.
The changing of paths of light.
Explanation:
I have explained in the image attached below.
From the explanation, the correct ones are;
The dilation of time.
The falling of objects.
The changing of paths of light.
Answer: v = 3.57×10^6 m/s; R = 4.42×10^-3m; T = 7.78×10^-9 s
Explanation:
Magnetic force(B) = 4.60×10^-3 T
Electric force(E) = 1.64×10^4 V/m
Both forces having equal magnitude ;
Magnetic force = electric force
qvB = qE
vB = E
v = (1.64×10^4) ÷ (4.60×10^-3)
v = 3.57×10^6 m/s
2.) Assume no electric field
qvB = ma
Where a = v^2 ÷ r
R = radius
a = acceleration
v = velocity
qvB = m(v^2 ÷ R)
R = (m×v) ÷ (|q|×B)
q=1.6×10^-19C
m = 9.11×10^-31kg
R = (9.11×10^-31 * 3.57×10^6) ÷ (1.6×10^-19 * 4.6×10^-3)
R = 32.5227×10^-25 ÷ 7.36×10^-22
R = 4.42×10^-3m
3.) period(T)
T = (2*pi*R) ÷ v
T = (2* 4.42×10^-3 * 3.142) ÷ (3.57×10^6)
T = (27.775×10^-3) ÷(3.57×10^6)
T = 7.78×10^-9 s
Answer:
The impulse transferred to the nail is 0.01 kg*m/s.
Explanation:
The impulse (J) transferred to the nail can be found using the following equation:
Where:
: is the final momentum
: is the initial momentum
The initial momentum is given by:
Where 1 is for the hammer and 2 is for the nail.
Since the hammer is moving down (in the negative direction):
And because the nail is not moving:
Now, the final momentum can be found taking into account that the hammer remains in contact with the nail during and after the blow:
Since the hammer and the nail are moving in the negative direction:
= 
= -9.7 m/s
Finally, the impulse is:
Therefore, the impulse transferred to the nail is 0.01 kg*m/s.
I hope it helps you!
