Answer:
The false statement is in option 'd': The center of mass of an object must lie within the object.
Explanation:
Center of mass is a theoretical point in a system of particles where the whole mass of the system is assumed to be concentrated.
Mathematically the position vector of center of mass is defined as
where,
is the position vector of the mass dm.
As we can see for homogenous symmetrical objects such as a sphere,cube,disc the center of mass is located at the centroid of the shapes itself but in many shapes it is located outside the body also.
Examples of shapes in which center of mass is located outside the body:
1) Horseshoe shaped body.
2) A thin ring.
In many cases we can make shapes of bodies whose center of mass lies outside the body.
Answer:
a) false b) true c) true d) false and e) true
Explanation:
a) false. All the energy applied is used for the phase change, so the temperature remains constant.
b) true. The kinetic energy is associated with the speed of the particles and they have more mobility in the liquid, therefore, more kinetic energy.
c) true. Since energy is used for state change
d) false. In general, mobility and temperature are proportional
e) true. Heat is the source of energy for the change of state
Answer:Expression given below
Explanation:
Given mass of spring
Compression in the spring
Let the spring constant be K
Using Energy conservation
potential energy stored in spring =Kinetic energy of Block
now conserving momentum
where is the final velocity
Impulse = Change in momentum.
The ball was moving with a momentum of 0.45 * 22 = 9.9
The ball comes to rest in the receivers arm; this means the ball's final velocity = 0. So mv2 = 0.45 * 0
The magnitude of the impact is just the change in momentum. 9.9 - (0.45 * 0) = 9.9