Answer:
240 cm³
Explanation:
Weight = Buoyancy
mg = ρVg
m = ρV
(0.9 g/cm³ × 2400 cm³) = (1 g/cm³) V
V = 2160 cm³
The submerged volume is 2160 cm³, so the volume above the surface is 240 cm³.
Answer:
(a) a = (2i + 4.5j) m/s^2
(b) r = ro + vot + (1/2)at^2
Explanation:
(a) The acceleration of the particle is given by:

vo: initial velocity = (3.00i -2.00j) m/s
v: final velocity = (9.00i + 7.00j) m/s
t = 3s
by replacing the values of the vectors and time you obtain:
![\vec{a}=\frac{1}{3s}[(9.00-3.00)\hat{i}+(7.00-(-2.00))\hat{j}]\\\\\vec{a}=(2\hat{i}+4.5\hat{j})m/s^2](https://tex.z-dn.net/?f=%5Cvec%7Ba%7D%3D%5Cfrac%7B1%7D%7B3s%7D%5B%289.00-3.00%29%5Chat%7Bi%7D%2B%287.00-%28-2.00%29%29%5Chat%7Bj%7D%5D%5C%5C%5C%5C%5Cvec%7Ba%7D%3D%282%5Chat%7Bi%7D%2B4.5%5Chat%7Bj%7D%29m%2Fs%5E2)
(b) The position vector is given by:

where vo = (3.00i -2.00j) m/s and a = (2.00i + 4.50j)m/s^2
Answer:
When the temperature of the coffee is 50 °C, the time will be 20.68 mins
Explanation:
Given;
The initial temperature of the coffee T₀ = 95 °C
The temperature of the room = 21°C
Let T be the temperature at time of cooling t in mins
According to Newton's law of cooling;

When the temperature is 50 °C, the time t in min is calculated as;

Therefore, when the temperature of the coffee is 50 °C, the time will be 20.68 mins
Answer
I think most see black and white.
Use SUVAT where:
S = distance
U = initial velocity = 30m/s
V = end velocity = 0 m/s
A = acceleration = ?
T = time = 5 secs
then pick out the equation v = u + at
so:
0 = 30 + 5a
-30 / 5 = a
a = -6 m/s^2