<em>Quantities that determine the kinetic energy of a body are its </em><em>mass and velocity </em>
Answer: <em>mass and velocity </em>
Explanation:
The kinetic energy of a body is the energy possessed by an object by virtue of its motion. It is given by the equation
Where m represents mass of the body and v represents its velocity.
Two bodies of equal velocity but different mass the heavier body will have greater kinetic energy. When an object is at rest its velocity is equal to zero. Thus its kinetic energy will be zero. Hence it can be concluded that only moving bodies have kinetic energy.
Stationary objects placed at a height possess potential energy which is the energy by virtue of their position or configuration. The total mechanical energy of a system is the sum of potential and kinetic energy.
Answer:
the initial speed of the arrow before joining the block is 89.85 m/s
Explanation:
Given;
mass of the arrow, m₁ = 49 g = 0.049 kg
mass of block, m₂ = 1.45 kg
height reached by the arrow and the block, h = 0.44 m
The gravitational potential energy of the block and arrow system;
P.E = mgh
P.E = (1.45 + 0.049) x 9.8 x 0.44
P.E = 6.464 J
The final velocity of the system after collision is calculated as;
K.E = ¹/₂mv²
6.464 = ¹/₂(1.45 + 0.049)v²
6.464 = 0.7495v²
v² = 6.464 / 0.7495
v² = 8.6244
v = √8.6244
v = 2.937 m/s
Apply principle of conservation of linear momentum to determine the initial speed of the arrow;
Therefore, the initial speed of the arrow before joining the block is 89.85 m/s
Answer: the child's centripetal acceleration=24.50 m/s²
Explanation:
Given that mass of child= 50 kg
radius of merry go round= 2.25m
angular speed = 3.30 rad/s
Centripetal Acceleration = v²/ r
But V= ωr
So Centripetal Acceleration = v²/ r = (ωr)²/ r
=(3.30)² x (2.25)²/ 2.25 = (3.30)² x 2.25
=24.5025m/s²
=24.50 m/s²
Answer:
We can conclude by saying that in the beginning current will increase but after sometime, it becomes saturated.
Explanation:
Note: No information on change in number of electron generated.
Since there is a collision, the electrons emitted will not reach the collector at same time. As the voltage is increased, the the speed with which the electrons will reach the collector starts to increase. Due to this, electric current will first increases till all the emitted electrons reach the collector. Since we are not provided with the information that number of electrons generated are changing, after increasing voltage current will increase for some time and then reaches a saturated state.
We can conclude by saying that in the beginning current will increase but after sometime it becomes saturated.
Answer:
The maximum height the pumpkin reaches occurs at 62.5 horizontal meters from its launching spot.
Explanation:
Notice that we are given the actual trajectory equation:
which corresponds to a curve represented by a parabola.
We can find the maximum of this parabola with arms pointing down requesting the derivative (slope of the tangent line to the curve) to be zero :
