The kangaroo reaches a maximum vertical altitude of 2.8 m, which can be calculated using the formula 2.8 = 1/2 * 9.8 * t^2. Thus, applying the equation s = ut + 1/2at^2.
1 hour = 3,600 seconds
1 km = 1,000 meters
75 km/hour = (75,000/3,600) m/s = 20-5/6 m/s
The mean speed during the deceleration is
(1/2)(20-5/6 + 0) = 10-5/12 m/s.
Traveling at this average speed for 21 seconds,
the bus covers
(10-5/12) × (21) = 218.75 meters.
Answer:
A) and B) are valid.
Explanation:
When an object remains at rest, it is indicative that no net force acts upon it.
The downward gravitational force from Earth must be counterbalanced by an upward force of equal magnitude in order to maintain rest.
This upward force is provided by the normal force, which adjusts to satisfy Newton’s 2nd Law and is always perpendicular to the surface supporting the object (in this instance, the ground).
At the molecular level, this normal force comes from the ground's bonded molecules acting like tiny springs, compressed by the object’s molecules, providing an upward restorative force.
Thus, statements A) and B) are true.
Answer:
The distance covered by the minutes hand is 39.60 cm.
Explanation:
Note: A clock has a circular shape, where the minutes hand acts as the radius, and its motion creates an arc.
Length of an arc is calculated as ∅/360(2πr)
L = ∅/360(2πr).................... Equation 1π
Here, L represents the arc’s length, ∅ is the angle made by the arc, and r is the arc’s radius.
Given: ∅ = 252°, r = 9 cm, π = 3.143.
Upon substituting these values into equation 1,
L = 252/360(2×3.143×9)
L = 0.7×2×3.143×9
L = 39.60 cm.
Thus, the distance traversed by the minutes hand is 39.60 cm.
<span>E = h x f </span>
<span>Thus: </span>
<span>f = E / h </span>
<span>f = 4.41•10^-19 / 6.62•10^-34 </span>
<span>f = 6.66•10^14 Hz (s^-1) </span>
<span>b/ What is the wavelength of this light? </span>
<span>------------------------------ </span>
<span>λ = c / f </span>
<span>λ = 3•10^8 / 6.66•10^14 </span>
<span>λ = 4.50•10^-7 m </span>
