Answer:
four seconds
Explanation:
A player who catches the ball and is being closely guarded may hold the ball for four seconds, then dribble the ball for four seconds, then hold the ball for another four seconds, then pass, will not be in violation of this rule.
Answer:
0.37 m/s to the left
Explanation:
Momentum is conserved. Initial momentum = final momentum.
m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂
Initially, both the fisherman/boat and the package are at rest.
0 = m₁ v₁ + m₂ v₂
Plugging in values and solving:
0 = (82 kg + 112 kg) v + (15 kg) (4.8 m/s)
v = -0.37 m/s
The boat's velocity is 0.37 m/s to the left.
You haven't told us anything about the detectors being used. We don't know how the sensitivity of the detector is related to the total number of photons absorbed, and we don't even know whether you and your friend are both using the same type of detector.
All we can do, in desperation, is ASSUME that the minimum time required to just detect a star is inversely proportional to the total number of its photons that strike the detector. That is, assume . . .
(double the number of photons) ===> (detect the source in half the time) .
-- The intensity of light delivered to the prime focus of a telescope is directly proportional to the AREA of its objective lens or mirror, which in turn is proportional to the square of its radius or diameter.
So your telescope gathers (0.18/0.05)² = 12.96 times as much light as your friends telescope does.
-- So we'd expect your instrument to detect the same star in
(119.5 min) / (12.96) = <em>9.22 minutes .</em>
We're simply comparing the performance of two different telescopes as they observe the same object, so the star's magnitude doesn't matter.
Answer:
m = 2.2 x 10⁻⁴ kg = 0.22 g
Explanation:
The surface tension of water is 0.072 N/m. So in order for the bug to avoid sinking, its weight per unit length of contact must be no more than the surface tension of water. Therefore,
where,
m = mass of bug = ?
g = acceleration due to gravity = 9.81 m/s²
L = Contact length = (contact length of each leg)(No. of Legs) = (5 mm)(6)
L = 30 mm = 0.03 m
Therefore,
<u>m = 2.2 x 10⁻⁴ kg = 0.22 g</u>
Answer:
F = 5702.56 N
Explanation:
Given that,
Mass of a small car, m = 800 kg
Initial speed of the car, u = 27.8 m/s
Final speed, v = 0
Time, t = 3.9 s
We need to find the force did it take for the car to stop.
The force acting on an object is given by :
So, the magnitude of force acting on the car to stop is 5702.56 N.
