Answer:
B. 81
Explanation:
When you multiply two numbers, round the answer to the least number of significant figures available. 67.6 has three significant figures, and 1.2 has two significant figures. So we round to two significant figures.
Answer:As an object speeds up, the total energy increases / decreases / remains the same. As an object slows down, the total energy increases / decreases / remains the same.
Explanation:
Ek = 1/2 mv^2
9 × 10^4 = 1/2 × 800 × v^2
9 × 10^4/400 = 400 v^2 / 400
9 × 10^4/400 = v^2
√225 = v
15 ms⁻¹ = v
That's the only way I know how to work it out
I think in this case velocity and speed would be considered the same because me
s = d/t and v=d/t
one is distance travelled and the other is displacement of a body
Answer:
2000 kg m/s
Explanation:
The momentum of an object is a vector quantity whose magnitude is given by
where
m is the mass of the object
v is the velocity of the object
and its direction is the same as the velocity.
In this problem, we have:
- Spaceship 1 has
m = 200 kg (mass)
v = 0 m/s (zero velocity)
So its momentum is
- Spaceship 2 has
m = 200 kg (mass)
v = 10 m/s (velocity)
So its momentum is
Therefore, the combined momentum of the two spaceships is
