All categories

3 years ago

Which has more thermal energy: lake or a cup of hot chocolate?

1 answer:

4 0

Though the hot cocoa would have a higher temperature, the lake would have more thermal energy because it has more molecules with a greater total internal energy.

You might be interested in

(a) A force F = (3xî + 4yĵ), where F is in newtons and x and y are in meters, acts on an object as the object moves in the x-dir

ExtremeBDS [4]

Answer:

W = 53.6648 J

Explanation:

W = ∫ F * dr

F = < 4*x i , 3*y j > Newtons

dr = < dx, 0 >

Take the dot product:

F * dr = 4* x * dx

Now replacing numeric

W = ∫ 4 * x * dx , ║ x = ( 0 m ⇒ 5.18 m )

W = ¹ / ₂ * (4 N/m) * x ²

W = (2 N/m) * (5.18 m)²

W = 53.6648 J

8 0

3 years ago

A hot-air balloon is descending at a rate of 2.1 m/s when a passenger drops a camera. If the camera is 42 m above the ground whe

zysi [14]

Answer:

a) 2.7s

b) 29 m/s

Explanation:

The equation for the velocity and position of a free fall are the following

$v=v_{0}-gt$ -(1)

$x=x_{0}+v_{0}t-gt^{2}/2$ - (2)

Since the hot-air ballon is <em>descending </em>at 2.1m/s and the camera is dropped at 42 m above the ground:

$v_{0}=-2.1m/s$

$x_{0}=42m$

To calculate the time which it takes to reach the ground we use eq(2) with x=0, and look for the positive solution of t:

$t = \frac{1}{84}(2.1\pm\sqrt{2.1^{2} - 4\times42\times9.81/2} )$

t = 2.71996

Rounding to two significant figures:

t = 2.7 s

Now we calculate the velocity the camera had just before it lands using eq(1) with t=2.7s

$v=-2.1-9.81*(2.71996)$

v = -28.782 m/s

Rounding to two significant figures:

v = -29 m/s

where the minus sign indicates the downwards direction

3 0

3 years ago

The relationship between electricity and magnetism is called what

Leno4ka [110]

The relationship between electricity and magnetism is called<span> electromagnetism.</span>

5 0

3 years ago

How does light energy work

OLEGan [10]

Answer:

Light consists of photons, which are produced when an object's atoms heat up. Light travels in waves and is the only form of energy visible to the human eye.

Explanation:

6 0

3 years ago

Read 2 more answers

An astronaut of mass m in a spacecraft experiences a gravitational force F=mg when stationary on the launchpad.

zaharov [31]

gravitational force is the attraction force of earth on an object which is near the surface of earth

It will not depend on the velocity or acceleration of earth

So it will not change while an object is stationary or it is moving with some acceleration

So here we will say that force will remain the same

$F = mg$

7 0

3 years ago