Answer:
Option C
Explanation:
Kinetic energy is the energy that the body possesses by virtue of its motion.
The formula for Kinetic energy is given by 
Using this formula let us find kinetic energy for the bodies given and find out which is the greatest
A) KE = 
B) KE =
C) KE = 
D) KE = 
Comparing these we find that 9mv^2 is the highest.
Hence option C is the answer.
Answer:
do not worry bro you will know how to use it
Answer:
Work done by the gardner is 500 J
Explanation:
As we know that the gardner apply force perpendicular upward by magnitude 300 N and along the floor horizontal force is 100 N
so we have

now the displacement of the gardner along the floor is

now work done is given as

so we have


Answer:
A 35 m/s
Explanation:
Speed of any object is scalar quantity while velocity is a vector. The scalar quantity is represented only by magnitude it doesn't need direction.
Hence, option A is correct as all other options have direction as well.
Answer:
(a) θ = 55.85 degree
(b) 7.89 km
Explanation:
Using vector notations
A = 1.88 km south = 1.88 (- j) km = - 1.88 j km
B = 9.05 km 47 degree north of east
B = 9.05 ( Cos 47 i + Sin 47 j) km
B = (6.17 i + 6.62 j) km
Net displacement is
D = A + B
D = - 1.88 i + 6.17 i + 6.62 j = 4.29 i + 6.62 j
(a) Angle made with positive X axis
tanθ = 6.62 / 4.29 = 1.474
θ = 55.85 degree
(b) distance = 
distance = 7.89 km