A Sled of Mass M Is Coasting on the Icy

question 60

Multiple Choice

A sled of mass m is coasting on the icy surface of a frozen river. While it is passing under a bridge, a package of equal mass m is dropped straight down and lands on the sled (without causing any damage) . The sled plus the added load then continue along the original line of motion. How does the kinetic energy of the (sled + load) compare with the original kinetic energy of the sled?

• A)It is 1/4 the original kinetic energy of the sled.
• B)It is 1/2 the original kinetic energy of the sled.
• C)It is 3/4 the original kinetic energy of the sled.
• D)It is the same as the original kinetic energy of the sled.
• E)It is twice the original kinetic energy of the sled.

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Definitions:

Ala-Ser

Represents a dipeptide made of two amino acids, alanine and serine, linked by a peptide bond.

2,4-dinitrofluorobenzene

A chemical compound featuring a benzene ring substituted with two nitro groups (NO2) at the 2 and 4 positions and a fluorine atom at the 1 position.

N-terminal

Refers to the start of a protein or polypeptide terminated by an amino acid with a free amine group.

Amino Acid

A building block of proteins, characterized by an amino group (-NH2), a carboxyl group (-COOH), and a specific side chain.