Answer:
Momentum is define as the product of the mass and velocity of a body. It is measured in Kgm/s.
Explanation:
Momentum is the product of mass and velocity of an object. When an object or a body of mass 'm' is moving with velocity 'v', then its momentum can be determined as;
momentum (P) = mass × velocity
i.e P = m × v
= mv
It is measured in Kgm/s.
The change in momentum of a body is referred to as its impulse (Ft).
ΔP = m(v - u) = Ft
Where: P is the momentum of the object, m is its mass, v is its final velocity, u is the initial velocity, F is the force and t is the time in which the force acts.
Work done by the car is 3900 J
Explanation:
- Power and work are related by the equation, Power = Work Done/Time
- Power is the rate at which work is done.
- Here, the car uses power of 260 W and time taken is 15 s.
Work Done = Power × Time
= 260 × 15 = 3900 J
Answer:
Astronomer
Explanation:
A scientist who studies the objects in the sky, including planets, galaxies, black holes, and stars, is called an astronomer. These days, the terms astronomer and astrophysicist are used interchangeably, to talk about any physicist who specializes in celestial bodies and the forces that affect them.
The statement shows a case of rotational motion, in which the disc <em>decelerates</em> at <em>constant</em> rate.
i) The angular acceleration of the disc (
), in revolutions per square second, is found by the following kinematic formula:
(1)
Where:
- Initial angular speed, in revolutions per second.
- Final angular speed, in revolutions per second.
- Time, in seconds.
If we know that
,
y
, then the angular acceleration of the disc is:


The angular acceleration of the disc is
radians per square second.
ii) The number of rotations that the disk makes before it stops (
), in revolutions, is determined by the following formula:
(2)
If we know that
,
y
, then the number of rotations done by the disc is:

The disc makes 3.125 revolutions before it stops.
We kindly invite to check this question on rotational motion: brainly.com/question/23933120
Answer:

Explanation:
To solve this problem, we can use the following suvat equation:

where
is the vertical displacement of the frog
is the initial vertical velocity
t is the time
a is the acceleration
We have chosen this formula because apart from
, all the other quantities are known. In fact:
is the vertical displacement
t = 2 s is the total time of flight
is the acceleration due to gravity (negative because it is downward)
Therefore, solving for
, we find the initial velocity of the frog:
