Answer:
cần cung cấp 70 độ vì nước sôi ở 100°C
Explanation:
Answer:
(a) 10 m/s
(b) 22.4 m/s
Explanation:
(a) Draw a free body diagram of the car when it is at the top of the loop. There are two forces: weight force mg pulling down, and normal force N pushing down.
Sum of forces in the centripetal direction (towards the center):
∑F = ma
mg + N = mv²/r
At minimum speed, the normal force is 0.
mg = mv²/r
g = v²/r
v = √(gr)
v = √(10 m/s² × 10.0 m)
v = 10 m/s
(b) Energy is conserved.
Initial kinetic energy + initial potential energy = final kinetic energy
½ mv₀² + mgh = ½ mv²
v₀² + 2gh = v²
(10 m/s)² + 2 (10 m/s²) (20.0 m) = v²
v = 22.4 m/s
Answer:
20m/s due east
Explanation:
Given parameters:
Displacement eastward = 200m
Time = 10s
Unknown:
Velocity = ?
Solution:
Velocity is the displacement divided by time;
Velocity =
Velocity =
= 20m/s due east
A) 8.11 m/s
For a satellite orbiting around an asteroid, the centripetal force is provided by the gravitational attraction between the satellite and the asteroid:

where
m is the satellite's mass
v is the speed
R is the radius of the asteroide
h is the altitude of the satellite
G is the gravitational constant
M is the mass of the asteroid
Solving the equation for v, we find

where:




Substituting into the formula,

B) 11.47 m/s
The escape speed of an object from the surface of a planet/asteroid is given by

where:




Substituting into the formula, we find:

Answer:
a) uranium
b) deuterium
Explanation:
For the first question, you can actually know this by simple logic. The nucleus of Ucranium, has more energy than a pair of deuterium. Ucranium has a mass number and atomic mass higher than deuterium, therefore, when you do a fission with ucranium in it's nucleous, this would be in energy higher than the deuterium.
However, in terms of mass only, the fissioning of 1 gram of Deuterium will produce more energy than 1 gram of uranium, basically because deuterium is lighter and has a lower molecular weight than ucranium. This means that because of this lower molecular weight, in 1 gram of deuterium will contain more number of atoms than in 1 g of uranium. The interaction with these atoms, will produce more energy than the energy produced by uranium.