Sure !
The work is (weight of the book) x (height of the desk above the floor).
The force (weight) is the result of gravity.
It was gravity that did the work.
Given :
You drive 200 miles in 3 hours before stopping for lunch and gas. After lunch you travel 250 miles in an hour and a half.
To Find :
Average speed.
Solution :
We know, average speed is given by :

Therefore, average speed of the journey is 100 miles/hr.
Hence, this is the required solution.
Answer:
Explanation:
for rolling motion down the plane acceleration is given by the following expression
a = g sinθ / (1 + k² / R²)
here k is radius of gyration and R is radius of the object rolling down .
for cylinder I = 1/2 m R²
so k² = R² / 2
k² / R² = 1/2
a = g sinθ /( 1 + 1 / 2 )
= 2 / 3 x g sinθ
v = √ 2 a s
= √ (2 x 2 / 3 x g sinθ s )
= √ (4 / 3 x g h )
= √ (4 / 3 x g x .5 )
= √ 2g / 3
for sphere I = 2/5 m R²
so k² = 2/5 R²
k² / R² = 2 / 5
a = g sinθ / (1 + 2 / 5)
= 5 / 7 x g sinθ
v = √ 2 a s
= √ (2 x 5 / 7 x g sinθ s )
= √ (10/7 x g h )
Given
√ (10/7 x g h ) = √ 2g / 3
10/7 x g h = 2g / 3
h = 14 / 30 m
= .47 m .
Answer:
electromagnetic waves only
Explanation:
I just took the test, Hope it helps!
Answer:
Friction force is independent of the direction of the contacting surfaces
Explanation:
It can go any way depending on how much force is being out on it.