Answer:
a. 2.5 X 10^-1
Explanation:
First of all we shall calculate the resistance of the bulb of 75W , 240 V .
power = V² /R , V is potential and R is resistance
75 = 240²/ R
R = 240²/ 75
= 768 ohm .
Now this bulb is used with 120 V
current = 120 / 768
= .15625 A
power = V X I
potential x current
= 120 x .15625
= 18.75 W.
comparing it with 75 W
the ratio
18.75 / 75
= 2.5 x 10⁻¹.
To solve this problem we will use the concepts of the moment of rotational inertia, angular acceleration and the expression of angular velocity.
The rotational inertia is expressed as follows:
Here,
m = Mass of the object
r = Distance from the rotational axis
The rotational acceleration in terms of translational acceleration is
Here,
a = Acceleration
R = Radius of the circular path of the object
The expression for the rotational speed of the object is
Here,
is the angular displacement of the object
The explanation by which when climbing a mountain uphill is changed to a larger pinion, is because it produces a greater torque but it is necessary to make more pedaling to be able to travel the same distance. Basically every turn results in less rotations of the rear wheel. Said energy that was previously used to move the rotation of the wheel is now distributed in more turns of the pedal. Therefore option a and c are correct.
This would indicate that the correct option is D.
Answer:
the acceleration of the car is -5 m/s².
Explanation:
Given;
initial velocity of the car, u = 50 m/s
time of motion, t = 6 s
final velocity of the car, v = 20 m/s
The acceleration of the car is calculated as;
Therefore, the acceleration of the car is -5 m/s².
Answer:
add a subscript of 4 after the O
Explanation:
The chemical formula of a compound is said to contain the elements in that compound with the respective number of atoms in each element. When writing chemical formula of a compound, the chemical symbols of each comprising element must be known. In this case involving Phosphorus tetraoxide, the symbols of the elements in this compound has been identified as P for Phosphorus and O for oxygen.
After identification of elemental symbols in the compound, Sebastian must now allocate the number of atoms that each element contains. According to the name of the compound, TETRA preceding oxygen means four (4), hence, four will be added as a subscript to O. Hence, at the end, the chemical formula will be PO4.
Please note that, the order of the chemical formula will go as the name implies Phosphorus tetraoxide, so phosphorus symbol (P) comes first, followed by oxygen symbol (O)
B. motion, because if a body isn’t moving and you apply a moving force to it it will then cause the body to be put into motion as well