Answer:
1.5 kgms⁻¹
Explanation:
Momentum can be defined as "<em>mass in motion</em>."
The amount of momentum that an object has is dependent upon two factors
- mass of the moving object
when there is a change in the velocity , it creates a change in momentum also
when we consider that we can mathematically show this,In terms of an equation,
Change in momentum (ΔΡ) = m(Δv)
where (Δv) - change in velocity
<em>(Δv) = final velocity - initial velocity</em>
Change in momentum (ΔΡ) = m(Δv)
= 0.1×([55-40])
= 1.5 kgms⁻¹
Answer:
D. the proper replacement unit for one joule per second
Explanation:
When energy is divided by the time the energy was used we get power
So, the answer is D. the proper replacement unit for one joule per second
An electric power measure the rate of electrical energy transfer by an electric circuit per unit of time.
Answer:
3.28 m
3.28 s
Explanation:
We can adopt a system of reference with an axis along the incline, the origin being at the position of the girl and the positive X axis going up slope.
Then we know that the ball is subject to a constant acceleration of 0.25*g (2.45 m/s^2) pointing down slope. Since the acceleration is constant we can use the equation for constant acceleration:
X(t) = X0 + V0 * t + 1/2 * a * t^2
X0 = 0
V0 = 4 m/s
a = -2.45 m/s^2 (because the acceleration is down slope)
Then:
X(t) = 4*t - 1.22*t^2
And the equation for speed is:
V(t) = V0 + a * t
V(t) = 4 - 2.45 * t
If we equate this to zero we can find the moment where it stops and begins rolling down, that will be the highest point:
0 = 4 - 2.45 * t
4 = 2.45 * t
t = 1.63 s
Replacing that time on the position equation:
X(1.63) = 4 * 1.63 - 1.22 * 1.63^2 = 3.28 m
To find the time it will take to return we equate the position equation to zero:
0 = 4 * t - 1.22 * t^2
Since this is a quadratic equation it will have to answers, one will be the moment the ball was released (t = 0), the other will eb the moment when it returns:
0 = t * (4 - 1.22*t)
t1 = 0
0 = 4 - 1.22*t2
1.22 * t2 = 4
t2 = 3.28 s
