Answer
(C).
When there is an angle between the two directions, the cosine of the angle must be considered.
Step by step Solution
The work done by a force is defined as the product of the force and the distance traveled in the direction of motion.
The first answer "Only the component of the force perpendicular to the motion is used to calculate the work" is wrong because, the force perpendicular to motion does no work.
The second choice "If the force acts in the same direction as the motion, then no work is done" is wrong because the work in the direction of the force is 
.
Fourth answer "A force at a right angle to the motion requires the use of the sine of the angle" is wrong because the 
meaning that there is no work done in the direction perpendicular to the motion.
The third answer" When there is an angle between the two directions, the cosine of the angle must be considered." is correct because the work is calculated using the force in the direction of the motion. The magnitude of this force is 
The correct option is (B) <span>Aluminum is a metal and is shiny, malleable, ductile, conducts heat and electricity, forms basic oxides, and forms cations in aqueous solution.
Since Aluminium is in group 13, and all the elements in group 13 are either metals or metalloids(Boron). Hence we are left with option (B) and (D). Boron is the only metalloid in group 13 and aluminium is a metal(not a metalloid); therefore, we are left with only one option which is Option (B). And Aluminium is </span>shiny, malleable, ductile, conducts heat and electricity, forms basic oxides, and forms cations in aqueous solution.<span>
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Answer:
the branch of science concerned with the nature and properties of matter and energy
Answer:
Explanation:
= Angular speed
= Distance of Mary = 11.5 ft
= Distance of Alex = 6 ft
Ratio of centripetal acceleration is given by
Mary's centripetal acceleration is 1.92 times the centripetal acceleration of Alex
Answer: The period of the pendulum will increase. Because of less gravity
Explanation:
Since the force of gravity is less on the Moon, the pendulum would swing slower at the same length and angle and its frequency would be less. Hence more time period will be experienced by the pendulum. On the moon, the acceleration due to gravity g is less when compared to that of the earth.
