A sprinter who is running a 200-m race travels the second 100 m in much less time than the first 100m because
2 answers:
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Answer: 24
Explanation:
Given the following equation:
Where is the number of mushrooms in a pizza and
the number of pizzas.
If we know the restaurant will make 8 pizzas (), then:
This is the needed number of mushrooms for 8 pizzas
Answer:
A. when the mass has a displacement of zero
Explanation:
The velocity of a mass on a spring can be calculated by using the law of conservation of energy. In fact, the total energy of the mass-spring system is equal to the sum of the elastic potential energy (U) of the spring and the kinetic energy (K) of the mass:
where
k is the spring constant
x is the displacement of the mass with respect to the equilibrium position of the spring
m is the mass
v is the velocity of the mass
Since the total energy E must remain constant, we can notice the following:
- When the displacement is zero (x=0), the velocity must be maximum, because U=0 so K is maximum
- When the displacement is maximum, the velocity must be minimum (zero), because U is maximum and K=0
Based on these observations, we can conclude that the velocity of the mass is at its maximum value when the displacement is zero, so the correct option is A.
- initial velocity=u=20km/h=5.5m/s
- Acceleration=a=8m/s^2
- Time=t=10s