Answer:
The minimum speed required is 5.7395km/s.
Explanation:
To escape earth, the kinetic energy of the asteroid must be greater or equal to its gravitational potential energy:
or
where 
is the mass of the asteroid, 
is its distance form earth's center, 
is the mass of the earth, and 
is the gravitational constant.
Solving for 
we get:
putting in numerical values gives
in kilometers this is
Hence, the minimum speed required is 5.7395km/s.
We want to find how much momentum the dumbbell has at the moment it strikes the floor. Let's use this kinematics equation:
Vf² = Vi² + 2ad
Vf is the final velocity of the dumbbell, Vi is its initial velocity, a is its acceleration, and d is the height of its fall.
Given values:
Vi = 0m/s (dumbbell starts falling from rest)
a = 10m/s² (we'll treat downward motion as positive, this doesn't affect the result as long as we keep this in mind)
d = 80×10⁻²m
Plug in the values and solve for Vf:
Vf² = 2(10)(80×10⁻²)
Vf = ±4m/s
Reject the negative root.
Vf = 4m/s
The momentum of the dumbbell is given by:
p = mv
p is its momentum, m is its mass, and v is its velocity.
Given values:
m = 10kg
v = 4m/s (from previous calculation)
Plug in the values and solve for p:
p = 10(4)
p = 40kg×m/s
Answer:
Explanation:
We shall apply law of conservation of momentum in space to know the velocity of combination after the impact
m₁v₁ = m₂v₂
.1 x 4 = ( 1 + .1 ) v₂
v₂ = .3636 m /s
1 )
Kinetic energy of the combination
= 1/2 x 1.1 x ( .3636)²
= 7.3 x 10⁻² J
2 )
Initial kinetic energy of the system
= 1/2 x 0.1 x 4²
= 0.8 J
Final kinetic energy of the system = 7.3 x 10⁻²
Loss of energy = .8 - .073
= .727 J
This energy was converted into internal energy of the system .
3 )
increase in entropy = dQ / T
Here dQ = .727 J
T = 300 ( Constant )
dQ / T = 2.42 X 10⁻³ J/K
Answer:
-1486 KJ
Explanation:
The work done by an electric field on a charged body is:
W = ΔV * q
where ΔV = change in voltage
q = total charge
The total charge of Avogadro's number of electrons is:
6.0221409 * 10^(23) * -1.6023 * 10^(-19) = -9.65 * 10^(4)
The change in voltage, ΔV, is:
9.20 - (6.90) = 15.4
Therefore, the work done is:
W = -9.65 * 10^(4) * 15.4 = -1.486 * 10^6 J = -1486 KJ
The negative sign means that the motion of the electrons is opposite the electrostatic force.
