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2 years ago

To heat the water in the tank from 50°C to 58°C the immersion heater transfers

Physics

1 answer:

LenKa [72]2 years ago

4 0

Let's see

∆T=58-50=8°C

$\\ \rm\Rrightarrow Q=mc\Delta T$

$\\ \rm\Rrightarrow 4032=4200(8)m$

$\\ \rm\Rrightarrow 4032/8=4200m$

$\\ \rm\Rrightarrow 504=4200m$

$\\ \rm\Rrightarrow m=0.12kg$

$\\ \rm\Rrightarrow m=120g$

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Find the specific gravity of the rose quartz. Specific gravity = density of of water.

Veronika [31]

It has no units. not sure.

6 0

2 years ago

A) Julie is running to the right at 5 m/s, as shown in the 1st figure. Balls 1 and 2 are thrown toward her at 10 m/s by friends

Svetach [21]

Part 1)

here Julie is running at speed 5 m/s

So here two balls are thrown at speed 10 m/s towards Julie with respect to her friend standing on the ground.

So here this all speed is real speed of all.

Now as per Anita (let say she is one of her friend standing on ground) the speed of two balls will be same as the given speed as she is observing from ground or stationary frame

As per the frame of Julie

speed of ball 1

$v_{1j} = v_1 - v_j$

$v_{1j} = 10 - 5 = 5 m/s$ towards her in same side

speed of ball 2

$v_{2j} = v_2 - v_j$

$v_{2j} = -10 - 5 = -15 m/s$ towards her from opposite side

Part b)

Now in this case the speed of two balls is given with respect to Julie

so we can say

for ball 1

$v_{1j} = v_1 - v_j$

$10 = v_1 - 5$

so in ground frame speed of ball 1 is

$v_1 = 15 m/s$

Similarly for ball 2

$v_{2j} = v_2 - v_j$

$-10 = v_2 - 5$

So speed in ground frame of ball 2 is

$v_2 = - 5 m/s$

so its 5 m/s from opposite side

6 0

3 years ago

Newton’s second law states that the acceleration a of an object is proportional to the force F acting on it is inversely proport

netineya [11]

Answer:

$[F]=[MLT^{-2}]$

Explanation:

Newton’s second law states that the acceleration a of an object is proportional to the force F acting on it is inversely proportional to its mass m. The mathematical expression for the second law of motion is given by :

F = m × a

F is the applied force

m is the mass of the object

a is the acceleration due to gravity

We need to find the dimensions of force. The dimension of force m and a are as follows :

$[m]=[M]$

$[a]=[LT^{-2}]$

So, the dimension of force F is, $[F]=[MLT^{-2}]$ . Hence, this is the required solution.

5 0

3 years ago

A rock has a specific gravity of 2.32 and a volume of 8.64 in3 how much does it weigh

lianna [129]

Answer: 3.21 N

$Specific\hspace{1mm} gravity = \frac {Density\hspace{1mm}of\hspace{1mm}substance}{Density\hspace{1mm} of \hspace{1mm}water}$

$\Rightarrow Density \hspace{1mm}of\hspace{1mm}substance= 2.32\times 1000\hspace{1mm} kg/m^3 = 2320\hspace{1mm}kg/m^3\\ Mass =Density\times volume\\ \Rightarrow 2320 \hspace{1mm} kg/m^3\times 8.64 \hspace{1mm}in^3\times \frac {1.64\times10^{-5} m^3}{1\hspace{1mm}in^3}=0.328 kg$

For weight, we will multiply by $g=9.8 m/s^{-2}$

$weight= 0.328\times9.8=3.21\hspace{1mm}N$

Hence, the rock would weigh 3.21 N.

3 0

2 years ago

Block A, with a mass of 4.0 kg, is moving with a speed of 2.0 m/s while block B , with a mass of 8.0 kg, is moving in the opposi

Anon25 [30]

Consider velocity to the right as positive.

First mass:
m₁ = 4.0 kg
v₁ = 2.0 m/s to the right

Second mass:
m₂ = 8.0 kg
v₂ = -3.0 m/s to the left

Total momentum of the system is
P = m₁v₁ + m₂v₂
= 4*2 + 8*(-3)
= -16 (kg-m)/s

Let v (m/s) be the velocity of the center of mass of the 2-block system.

Because momentum of the system is preserved, therefore
(m₁+m₂)v= -16
(4+8 kg)*(v m/s) = -16 (kg-m)/s
v = -1.333 m/s

Answer:
The center of mass is moving at 1.33 m/s to the left.

5 0

3 years ago