Question isn’t clear
If it’s asking the no of electrons then -
No of electrons =no of protons in an atom of a element ....therefore there are 11 electrons
Answer:
C. 98 J
Explanation:
Mechanical energy is defined as the sum of kinetic energy (K) and potential energy (U):
E = K + U
where
is the kinetic energy, where m is the mass of the object and v its speed
is the potential energy, where g is the gravitational acceleration and h the height of the object relative to a reference point
For the object in this problem, the kinetic energy is zero, because it is not moving, so v = 0 and K=0. So the mechanical energy is just given by the potential energy, which is given by:
A supersonic speed has a Mach number ranging from 1.2 to 5. Supersonic speed tells us that an object's rate of travel is faster than the speed of sound. The Mach number is a dimensionless ratio between velocity and the local speed of sound for an incompressible flow in liquids and gases. It is determined by the equation M = u/c where u is the local flow velocity and c is speed of sound in the medium.
Answer:
the ratio Kf : Ki is 1 / 4 or 1 : 4
Explanation:
Given the data in the question;
Since this is a perfectly inelastic collision, momentum is conserved;
=
Now for BLOCK 1
mass = M₁ = M
KE = K
mv₁² = K
we solve for v₁
mv₁² = 2K
v₁ = √( 2K / m )
for BLOCK 2
mass = M₂ = 3m and since its at rest v₂ = 0
Now after the collision; Total mass = m + 3m = 4m
KE = K
( 4m )v² = K
(2m)v² = K
v = √(K / 2m)
so since =
[m₁ × v₁] + [m₂ × v₂] = ( m + 3m ) × v
so
[ m₁ × √( 2K / m ) ] + [ m₂ × 0 ] = ( m + 3m ) × [ √(K / 2m) ]
[ m × √( 2K / m ) ] = 4m × [ √(K / 2m) ]
square both side
m² × 2K / m = (4m)² × K / 2m
m² × 2K / m = 16m² × K / 2m
m × 2K = 8m × K
2K = 8K
K = 2K / 8
K / K = 2 / 8
K / K = 1 / 4
Therefore, the ratio Kf : Ki is 1 / 4 or 1 : 4