Frost wedging occurs when water seeps into a crack in a rock, freezes, and causes the crack in the rock to widen.

Compare the temperature of water as ice begins to form with the temperature of ice as it begins to melt

liubo4ka [24]

They are the same temperature.

If you have 1 gram of ice at zero degrees C, you have to pump 334 joules
of heat energy into it in order to<em> just change it from solid to liquid</em> at the <em>same temperature. </em>

This is one of the highest figures known for any substance, and that's why
a piece of ice does such a good job cooling your drink.

3 0

3 years ago

What is the maximum speed (in units of m/s) with which a car can round a

IrinaK [193]

Answer:

B) 15.5 m/s

Explanation:

r = 60m

μs = 0.4

using the formula max V = √r*g*μs (flat roadway)

v = sqrt(60 * 10 * 0.4)

v = 15.5 m/s

5 0

3 years ago

A 92-kg fullback moving south with a speed of 5.8 m/s is tackled by a 110-kg lineman running west with a speed of 3.6 m/s. Assum

MariettaO [177]

Answer:

The speed and direction of the two players immediately after the tackle are 3.3 m/s and 53.4° South of West

Explanation:

given information:

mass of fullback, $m_{x}$ = 92 kg

speed of full back, $v_{x}$ = 5.8 to south

mass of lineman, $m_{y}$ =110 kg

speed of lineman, $v_{y}$ = 3.6

according to conservation energy,

assume that the collision is perfectly inelastic, thus

initial momentum = final momentum

$P_{ix}$ = $P_{x}$ '

m₁v₁ = (m₁+m₂) $v_{x}$ '

$v_{x}$ ' = m₁v₁/(m₁+m₂)

= (92) (5.8)/(92+110)

= 2.64 m/s

$P_{iy}$ = $P_{y}$ '

m₂v₂ = (m₁+m₂) $v_{y}$ '

$v_{y}$ ' = m₁v₁/(m₁+m₂)

= (110) (3.6)/(92+110)

= 1.96 m/s

thus,

$v$ ' = √ $v_{x}$ '²+ $v_{y}$ '²

= 3.3 m/s

then, the direction of the two players is

θ = 90 - tan⁻¹( $v_{y}$ '/ $v_{x}$ ')

= 90 - tan⁻¹(1.96/2.64)

= 53.4° South of West

7 0

3 years ago

A string is wrapped around a uniform disk of mass M = 1.2 kg and radius R = 0.07 m. (Recall that the moment of inertia of a unif

pentagon [3]

Explanation:

Given that,

Mass of disk = 1.2 kg

Radius = 0.07 m

Radius of rod = 0.11 m

Mass of small disk = 0.5 kg

Force = 29 N

Time t = 0.022 s

$\theta=0.023\ m$

Distance d= 0.039 m

(I). We need to calculate the speed of the apparatus

Using work energy theorem

$W=\Delta K.E$

$Fd=\dfrac{1}{2}mv^2$

$v=\sqrt{\dfrac{2Fd}{M+4m}}$

Where, m = total mass

v = velocity

F = force

d = distance

Put the value into the formula

$v=\sqrt{\dfrac{2\times29\times0.039}{1.2+4\times0.5}}$

$v=0.840\ m/s$

(b). We need to calculate the angular speed of the apparatus

Using formula of torque

$\tau=I\alpha$

$F\times=(\dfrac{1}{2}MR^2+4mb^2)\alpha$

$29\times0.07=(\dfrac{1}{2}\times1.2\times0.07^2+4\times0.5\times0.11^2)\alpha$

$\alpha=\dfrac{29\times0.07}{0.02714}$

$\alpha=74.79\ rad/s^2$

We need to calculate the angular speed of the apparatus

Using equation of angular motion

$\omega=\omega_{0}+\alpha t$

Put the value into the formula

$\omega=0+74.79\times0.022$

$\omega=1.645\ rad/s$

(c). We need to calculate the angular speed of the apparatus

Using equation of angular motion

$\omega_{0}^2=\omega^2+2\alpha t$

Put the value into the formula

$\omega_{0}^2=1.645^2+2\times74.79\times0.022$

$\omega=2.44\ rad/s$

Hence, This is required equation.

7 0

3 years ago

which of the following is an example of a compound machine. a. a bicycle chain. b. a coffee mug. c. a paper cutter

Ann [662]

A. a bicycle chain is an example of a compound machine

8 0

2 years ago