Answer: false
Explanation: the longer the period, the less thef= frequency
Crates is the correct answer because they create dents that make the bumps of mountains.
Answer:
work done = 500 J
option e is correct
Explanation:
given data
mass = 2 kg
acceleration = 2 m/s
coefficient of kinetic friction = 0.3
block D = 50 m
to find out
work
solution
we know that work done is
work done = f × d ...........1
here f is force and d is block i.e 50 m
so here
force , f - k mg =ma
f = 2 ( 2 + 0.3 ×10 )
f = 10 N
so from equation 1
work done = f × d
work done = 10 × 50
work done = 500 J
option e is correct
Answer:
Hoop will reach the maximum height
Explanation:
let the mass and radius of solid ball, solid disk and hoop be m and r (all have same radius and mass)
They all are rolled with similar initial speed v
by the law of conservation of energy we can write

for solid ball
![[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{ball}\omega^2= mgh_{ball}](https://tex.z-dn.net/?f=%5Btex%5D%5Cfrac%7B1%7D%7B2%7Dmv%5E2%2B%5Cfrac%7B1%7D%7B2%7DI_%7Bball%7D%5Comega%5E2%3D%20mgh_%7Bball%7D)
putting
in the above equation and solving we get

now for solid disk
![[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{disk}\omega^2= mgh_{disk}](https://tex.z-dn.net/?f=%5Btex%5D%5Cfrac%7B1%7D%7B2%7Dmv%5E2%2B%5Cfrac%7B1%7D%7B2%7DI_%7Bdisk%7D%5Comega%5E2%3D%20mgh_%7Bdisk%7D)
putting
in the above equation and solving we get

for hoop
![[tex]\frac{1}{2}mv^2+\frac{1}{2}I_{hoop}\omega^2= mgh_{hoop}](https://tex.z-dn.net/?f=%5Btex%5D%5Cfrac%7B1%7D%7B2%7Dmv%5E2%2B%5Cfrac%7B1%7D%7B2%7DI_%7Bhoop%7D%5Comega%5E2%3D%20mgh_%7Bhoop%7D)
putting
in the above equation and solving we get

clearly from the above calculation we can say that the Hoop will reach the maximum height
Explanation:
Those tools that helps to make our work easier ,faster and more convenient in our daily life it is called simple Machine.