What will be the weight of a man of mass 90kg when he is on a planet with acceleration due to gravity of 15ms-2?

Andrei [34K]

Answer:

The mass of the juice responsible for melting the ice is 949.043 grams.

Explanation:

By the First Law of Thermodynamics, we understand that juice releases heat to the ice, which turns into water under the assumption that interactions between the ice-juice system and surroundings are negligible and energy processes are done in steady-state. Since juice is done with water, its specific heat will be taken as of the water. The process is described by the following formula:

$m_{i} \cdot [c_{i}\cdot (T_{1}-T_{2}) - L_{f} + c_{w}\cdot (T_{2}-T_{3})] + m_{w} \cdot c_{w}\cdot (T_{4}-T_{3}) = 0$ (1)

Where:

$m_{i}$ - Mass of ice, in grams.

$m_{w}$ - Mass of the juice, in grams.

$c_{i}$ - Specific heat of ice, in joules per gram-degree Celsius.

$c_{w}$ - Specific heat of water, in joules per gram-degree Celsius.

$L_{f}$ - Latent heat of fusion, in joules per gram.

$T_{1}$ - Initial temperature of ice, in degrees Celsius.

$T_{2}$ - Melting point of water, in degrees Celsius.

$T_{3}$ - Final temperature of the ice-juice system, in degrees Celsius.

$T_{4}$ - Initial temperature of the juice, in degrees Celsius.

If we know that $m_{i} = 100\,g$ , $c_{i} = 2.090\,\frac{J}{g\cdot ^{\circ}C}$ , $c_{w} = 4.18\,\frac{J}{g\cdot ^{\circ}C}$ , $L_{f} = 334\,\frac{J}{g}$ , $T_{1} = -10\,^{\circ}C$ , $T_{2} = 0\,^{\circ}C$ , $T_{3} = 10\,^{\circ}C$ and $T_{4} = 20\,^{\circ}C$ , then the mass of the juice is:

$m_{w} = \frac{m_{i}\cdot [c_{i}\cdot (T_{1}-T_{2}) - L_{f} + c_{w}\cdot (T_{2}-T_{3})]}{c_{w} \cdot (T_{3}-T_{4})}$

$m_{w} = \frac{(100\,g)\cdot \left[\left(2.090\,\frac{J}{g\cdot ^{\circ}C} \right)\cdot (-10\,^{\circ}C) - 334\,\frac{J}{g} +\left(4.18\,\frac{J}{g\cdot ^{\circ}C} \right)\cdot (-10\,^{\circ}C) \right]}{\left(4.180\,\frac{J}{g\cdot ^{\circ}C} \right)\cdot (-10\,^{\circ}C)}$

$m_{w} = 949.043\,g$

The mass of the juice responsible for melting the ice is 949.043 grams.

5 0

3 years ago

a uniform electric field E=15 N/C points downwards. A particle with charge q=-0.15 C is placed in the electric field. What is th

Alex17521 [72]

Answer:

2.25 N upwards

Explanation:

Answer:

800 N/C to the right

Explanation:

The equation that relates force on a charge, electric field and charge is

$F=qE$

where

F is the force acting on the charge

q is the charge

E is the electric field

In this problem, we have

$E=15 N/C$ is the electric field

$q=-0.15 C$ is the charge

Substituting into the formula, we find the force

$F=(-0.15 C)(15 N/C)=-2.25 N$

Concerning the direction:

- The electric field and the force have same directions if the charge is positive

- The electric field and the force have opposite directions if the charge is negative

Here the charge is negative, so the electric field has opposite direction to the force: therefore, it must be upwards.

3 0

3 years ago

The strength of an electromagnet can be altered by

denpristay [2]

The strength of an electromagnet can be altered by increasing the number of coils around the core. The more times the coil is wrapped, the stronger the electromagnet is.

Your answer is: B) Increasing the number of coils around the core

Have an amazing day and stay hopeful!

3 0

3 years ago

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SOMEONE HELP PLEASE!!!!(15POINTS)

Bezzdna [24]

Answer: Friction

Explanation:

Friction is a force that opposes the motion of an object on another surface. For example, when a box is pushed along the floor, the floor exerts a frictional force on the box, "resisting" the motion of the box. This force is due to the contact between the molecules of the box and the molecules of the floor, and it is always directed against the direction of motion of the object (so, if the object is moving forward, friction acts backwards).

The magnitude of the friction force is given by:

$F=\mu N$

where $\mu$ is the coefficient friction, which is a number that depends on the materials of the two surfaces, and N is the normal reaction.

7 0

3 years ago

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The photosystem channels the excitation energy gathered by absorption of light by any one of the pigment molecules to a specific

Liono4ka [1.6K]

Food and oxygen.......

3 0

3 years ago