Isotopes of an element will contain the same number of protons and electrons but will differ in the number of neutrons they contain. In other words, isotopes have the same atomic number because they are the same element but have a different atomic mass because they contain a different number of neutrons
Spring potential energy:
E = 0.5 * k * x²
k spring constant
x spring compression
x = √(2 * E / k) = 0.7
Answer:
The torque is 0.31 Nm.
Explanation:
Electrical energy, E = 8400 J
time, t = 1 min
Angular speed, w = 2900 rpm = 303.53 rad/s
efficiency = 2/3 of input power
The toque is given by

Alfred Wegener believed that all of the continents were originally attached! By looking at the map, you can see that Africa and South America look like they were once joined. This 'super continent' was known as Pangaea. He also found fossils that proved his point.
Hope this helps :)