Answer: The tension in the string is zero
Explanation:
The work done by the engine is converted into kinetic energy of the motorbike+rider system:

where
W=6400 J is the work
m=200 kg is the mass of the system
v is the speed acquired by the motorbike
Rearranging the equation and substituting the numbers in, we find
P = m * v
v = {3i - 4j} = square root (3^2 + 4^2) = 5
P = 20 * 5
P = 100 kg m/s
Helium’s state when the decompressed
helium atoms expand and float up, making the rubber balloon expand around them
and float with them is gas.
<span>Helium is a chemical element with symbol He and atomic number 2. It is a
colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in
the noble gas group in the periodic table. Its boiling point is the lowest
among all the elements.</span>
We use the kinematic equations,
(A)
(B)
Here, u is initial velocity, v is final velocity, a is acceleration and t is time.
Given,
,
and
.
Substituting these values in equation (B), we get
.
Therefore from equation (A),

Thus, the magnitude of the boat's final velocity is 10.84 m/s and the time taken by boat to travel the distance 280 m is 51.63 s