<span>Nuclei of u-238 atoms are </span><span>unstable and spontaneously emit alpha particles.</span>
Answer:
v₂ = 7.6 x 10⁴ m/s
Explanation:
given,
speed of comet(v₁) = 1.6 x 10⁴ m/s
distance (d₁)= 2.7 x 10¹¹ m
to find the speed when he is at distance of(d₂) 4.8 × 10¹⁰ m
v₂ = ?
speed of planet can be determine using conservation of energy
K.E₁ + P.E₁ = K.E₂ + P.E₂
v₂ = 7.6 x 10⁴ m/s
To calculate the number of sig figs
1. Count ALL nonzero numbers
2. If the zero is between 2 numbers, count it
3. If in a decimal the zero is at the end, count it
4. In a decimal all the zeros before the first nonzero number are placeholders and don't count them
5. In a number greater than zero all zeros AFTER the last nonzero number are placeholders and don't count them.
A - 5
B - 2
C - 3
D - 1
E - 4
W = m.g = weight
g = Gme/Re**2 where G= universal gravitational constant , Re= radius of the earth
me= mass of the earth
therefore it weighs 16 times less
Acceleration means speeding up, slowing down, or changing direction. The graph doesn't show anything about direction, so we just have to examine it for speeding up or slowing down ... any change of speed.
The y-axis of this graph IS speed. So the height of a point on the line is speed. If the line is going up or down, then speed is changing.
Sections a, c, and d are all going up or down. Section b is the only one where speed is not changing. So we can't be sure about b, because we don't know if the track may be curving ... the graph can't tell us that. But a, c, and d are DEFINITELY showing acceleration.
