Explanation:
It is given that, the position of a particle as as function of time t is given by :

Let v is the velocity of the particle. Velocity of an object is given by :

![v=\dfrac{d[(8t+9)i+(2t^2-8)j+6tk]}{dt}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7Bd%5B%288t%2B9%29i%2B%282t%5E2-8%29j%2B6tk%5D%7D%7Bdt%7D)

So, the above equation is the velocity vector.
Let a is the acceleration of the particle. Acceleration of an object is given by :

![a=\dfrac{d[8i+4tj+6k]}{dt}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7Bd%5B8i%2B4tj%2B6k%5D%7D%7Bdt%7D)

At t = 0, 

Hence, this is the required solution.
The formula for force exerted on/by a spring is
F = k*e where k is the spring constant and x is the distance stretched from
unstrained position. This should allow you to find what you need.
Using F = k x e,
where k is the spring constant,
and e is the extension,
The F is her weight = 45 X 0.80
= 36 N
Sorry bro I just need points for my calculus exam
Answer:
Explanation:
heat lost by water will be used to increase the temperature of ice
heat gained by ice
= mass x specific heat x rise in temperature
1 x 2090 x t
heat lost by water in cooling to 0° C
= mcΔt where m is mass of water , s is specific heat of water and Δt is fall in temperature .
= 1 x 2 x 4186
8372
heat lost = heat gained
1 x 2090 x t = 8372
t = 4°C
There will be a rise of 4 degree in the temperature of ice.
Answer:
A. To find the mass flow rate.
We use= 220 x 0.355/ 60
= 1.3kg/s
B. Volume flowrate is = mass flowrate / density
But density is 1000kg/m³
= 1.3kg/s/ 1000kg/m³
= 0.0013m³/s
C. Flow speead at 1
= 0.0013m³/s / (2 x 10-2m)²
= 6.5m/s
D.flow speed at 2
0.0013m³/s / (8x 10-2m)²
=1.63m/s
E. Gauge pressure at point 1
= 152+ 1/1000 ( 1.63)²- 6.5² + 1000( 9.8) ( 0-1.35)
= 119kpa