Answer:
B) a leaf blown from a tree by the wind
Answer:
The dimension is L
Explanation:
Dimension analysis is a method of representing quantities majorly with respect to some fundamental quantities of mass (M), length (L), time (T).
A sphere has a definite volume which relates to its radius by:
V = 


In this equation
is a dimensionless quantity, and the unit of v is
.
But, metre is a measure of length, thus it has a dimension of L.
So that,
≅ 
Then,
= 
Find the cube root of both sides to have,
r = L
Therefore, the dimension of the radius of a sphere is L.
Explanation:
Given:
u = 20 m/s
a = 5 m/s^2
v = 30 m/s
t = ?
Use the first kinematic equation of motion:
v = u + at
t = (v - u)/a = 10/5 = 2 seconds
Ke = (1/2)mv²
m = 100kg, v = 10 km/s = 10*1000 = 10000m/s
Ke = (1/2)*100*10000
Ke = 500000 Joules
That would be the dump truck. Momentum depends on how heavy a certain object is in motion. The more weight it has the harder it is to stop.