Answer:
7.22 × 10²⁹ kg
Explanation:
For the material to be in place, the gravitational force on the material must equal the centripetal force on the material.
So, F = gravitational force = GMm/R² where M = mass of neutron star, m = mass of object and R = radius of neutron star = 17 km
The centripetal force F' = mRω² where R = radius of neutron star and ω = angular speed of neutron star
So, since F = F'
GMm/R² = mRω²
GM = R³ω²
M = R³ω²/G
Since ω = 500 rev/s = 500 × 2π rad/s = 1000π rad/s = 3141.6 rad/s = 3.142 × 10³ rad/s and r = 17 km = 17 × 10³ m and G = universal gravitational constant = 6.67 × 10⁻¹¹ Nm²/kg²
Substituting the values of the variables into M, we have
M = R³ω²/G
M = (17 × 10³ m)³(3.142 × 10³ rad/s)²/6.67 × 10⁻¹¹ Nm²/kg²
M = 4913 × 10⁹ m³ × 9.872 × 10⁶ rad²/s²/6.67 × 10⁻¹¹ Nm²/kg²
M = 48,501.942 × 10¹⁵ m³rad²/s² ÷ 6.67 × 10⁻¹¹ Nm²/kg²
M = 7217.66 × 10²⁶ kg
M = 7.21766 × 10²⁹ kg
M ≅ 7.22 × 10²⁹ kg
Choice-'a' is a slippery, misleading, ambiguous statement,
but it's less wrong than any of the other choices on this list.
15) C. The amount of each element that begins....
Answer:
el plomo será el más largo
Explanation:
Dado que;
longitud inicial (l1) = 4m
Longitud final l2
aumento de temperatura (θ) = 10 ° C
Coeficiente de expansión lineal α
Ahora para el hierro;
α = 11,7 x 10-6
Desde;
l2-l / l1θ = α
l2 = α l1θ + l1
l2 = l1 (αθ + 1)
l2 = 4 ((11,7 x 10-6 * 10) + 1)
l2 = 4.00044 m
Para el plomo
l2 = 4 ((27,3 x 10-6 * 10) + 1)
l2 = 4,00109 m
Para cobre
l2 = 4 ((16,7 x 10-6 * 10) + 1)
l2 = 4.000668 m
Por lo tanto, el plomo será el más largo
