Answer:
Explanation:
Consider the initial position of the frog (20 m above ground) as the reference position. All measurements are positive measured upward.
Therefore,
u = 10 m/s, initial upward velocity.
H = - 20 m, position of the ground.
g = 9.8 m/s², acceleration due to gravity.
Part (a)
When the frog reaches a maximum height of h from the reference position, its velocity is zero. Therefore
u² - 2gh = 0
h = u²/(2g) = 10²/(2*9.8) = 5.102 m
At maximum height, the frog will be 20 + 5.102 = 25.102 m above ground.
Answer: 25.1 m above ground
Part (b)
Let v = the velocity when the frog hits the ground. Then
v² = u² - 2gH
v² = 10² - 2*9.8*(-20) = 492
v = 22.18 m/s
Answer: The frog hits the ground with a velocity of 22.2 m/s
Answer:
Explained.
Explanation:
Let me explain the two cases in by one.
(1) When Person wearing a jacket, heat from his or her body is going to get trapped inside his or her jacket to keep this person warm when a thermometer is placed inside, it would indicate a higher temperature on the scale.
(2) When Jacket is Hanging in a closet, its temperature would be roughly close to room temperature and when we would place a thermometer it would not indicate any change on its scale.
Answer:
B
Explanation: Because conduction is when an object touches another object and convection happens with boiling water or the water cycle, the particles/water fall and rise.
5-a). Acceleration is a vector defined as the rate of change of velocity.
Its magnitude has units of [length/time²]. The SI unit is meter/second².
Its direction is the direction in which velocity is increasing.
5-b). The graph says that the object's speed is not changing.
When we look at any time, from zero to almost 50 minutes, the
object's speed is the same . . . 60 m/s . This will make it easy.
There are 60 seconds in a minute, so 30 minutes = 1,800 seconds.
In every one of those seconds, the object covered 60 meters.
It travelled a total of (60 m/s)·(1,800 s) = 108,000 meters (108 km) .
