A ranger in a national park is driving at 49 km/h when a deer jumps onto the road 67 m ahead of the vehicle. After a reaction time of t s, the ranger applies the brakes to produce a deceleration of 3.5 m/s2. What is the maximum reaction time al- lowed if the ranger is to avoid hitting the deer?

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A ranger in a national park is driving at 49 km/h when a deer jumps onto the road 67 m ahead of the vehicle. After a reaction time of t s, the ranger applies the brakes to produce a deceleration of 3.5 m/s2. What is the maximum reaction time al- lowed if the ranger is to avoid hitting the deer? Answer in units of s
with what speed must a ball be thrown vertically from ground level to rise to a maximum height of 50m?
Your starting place on a track is at the 30 centimeters mark. What is your new position if you move 10 centimeters to the left of this position?

Determine which of the following observations are testable. For those that are testable: • Write a hypothesis and null hypothesis

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Determine which of the following observations are testable. For those that are testable:
•
Write a hypothesis and null hypothesis
• What would be your experimental approach?
• What are the dependent and independent variables?
• What is your control?
• How will you collect your data?
• How will you present your data (charts, graphs, types)?
• How will you analyze your data?
1. When a plant is placed on a window sill, it grows faster than when it is placed on a coffee
table in the middle of the living room.
2. The teller at the bank with brown hair is taller than the other tellers.
3. I caught four fish at seven o’clock in the morning but didn’t catch any at noon.
4. The salaries at Smith and Company are based on the number of sales. Billy makes 3,000
dollars more than Joe.
5. When Sally eats healthy foods and exercises regularly, her blood pressure is lower than
when she does not exercise and eats fatty foods.
4. The salaries at Smith and Company are based on the number of sales. Billy makes 3,000
dollars more than Joe.
5. When Sally eats healthy foods and exercises regularly, her blood pressure is lower than
when she does not exercise and eats fatty foods.
6. The Italian restaurant across the street closes at 9 pm but the one two blocks away closes
at 10 pm.
7. Bob bought a new blue shirt with a golf club on the back for twenty dollars.
8. For the past two days, the clouds have come out at 3 pm and it has started raining at 3:15
pm.
9. George did not sleep at all last night because he was up finishing his paper.
10. Ice cream melts faster on a warm summer day than on a cold winter day.
11. How can you apply the scienfic method to an everyday problem? Give one example.

An astronaut of mass 120 kg recedes from her spacecraft by activating a small propulsion unit attached to her back. The force generated by a spurt is 30 N. Show that her acceleration is 0.25 m/s2.

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40) 40. An astronaut of mass 120 kg recedes from her spacecraft
by activating a small propulsion unit attached to her
back. The force generated by a spurt is 30 N. Show that
her acceleration is 0.25 m/s2.
42. Sophia exerts a steady 40-N horizontal force on a 8-kg
box resting on a lab bench. The box slides against a horizontal
friction force of 24 N. Show that the box accelerates
at 2 m/s2
44. A rocket of mass 100,000 kg undergoes an acceleration
of 2 m/s2. Show that the net force acting on it is
200,000 N
69. If it were not for air resistance, would it be dangerous to
go outdoors on rainy days? Defend your answer
Disscusion Question
98. On which of these hills does the ball roll down with
increasing speed and decreasing acceleration along the
path? (Use this example if you wish to explain to someone
the difference between speed and acceleration.)
99. If you drop an object, its acceleration toward the ground
is 10 m/s2. If you throw it down instead, will its acceleration
after leaving your hand be greater than 10 m/s2?
Ignore air resistance. Defend your answer.
100. Can you think of a reason why the acceleration of the
object thrown downward through the air in the preceding
question would actually be less than 10 m/s2?

An astronaut of mass 120 kg recedes from her spacecraft by activating a small propulsion unit attached to her back. The force generated by a spurt is 30 N. Show that her acceleration is 0.25 m/s2.

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40) 40. An astronaut of mass 120 kg recedes from her spacecraft
by activating a small propulsion unit attached to her
back. The force generated by a spurt is 30 N. Show that
her acceleration is 0.25 m/s2.
42. Sophia exerts a steady 40-N horizontal force on a 8-kg
box resting on a lab bench. The box slides against a horizontal
friction force of 24 N. Show that the box accelerates
at 2 m/s2
44. A rocket of mass 100,000 kg undergoes an acceleration
of 2 m/s2. Show that the net force acting on it is
200,000 N
69. If it were not for air resistance, would it be dangerous to
go outdoors on rainy days? Defend your answer
Disscusion Question
98. On which of these hills does the ball roll down with
increasing speed and decreasing acceleration along the
path? (Use this example if you wish to explain to someone
the difference between speed and acceleration.)
99. If you drop an object, its acceleration toward the ground
is 10 m/s2. If you throw it down instead, will its acceleration
after leaving your hand be greater than 10 m/s2?
Ignore air resistance. Defend your answer.
100. Can you think of a reason why the acceleration of the
object thrown downward through the air in the preceding
question would actually be less than 10 m/s2?

40) Find the net force produced by a 30-N force and a 20-N force in each of these cases: (a) Both forces act in the same direction.

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40) Find the net force produced by a 30-N force and a 20-N force in each of these cases:
(a) Both forces act in the same direction.
(b) The two forces act in opposite directions.
45) A horizontal force of 120N is required to push a bookcase across a floor of constant velocity
(a) What is the net force acting on the bookcase?
(b) How much is the friction force that acts on the sliding bookcase?
(c) How much friction acts on the bookcase when it is at rest on a horizontal surface without being pushed?
48) (a) Show the average speed of a tennis ball is 48 m/s when it travel the full length of the court, 24m in 0.5 s.
49) (a) Show the average speed that the average speed of Leslie is 10 km/h when she runs to the store 5km away in 30min
50) (a) Show that the acceleration is 7.5 m/s for a ball that starts from rest and rolls down a ramp and gains a speed of 30 m/s in 4s.

a. If the Volume of the vessel is 20 then we know that the maximum amount of displaced fluid will be [v] units?

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a.
If the Volume of the vessel is 20 then we know that the maximum amount of displaced fluid will be [v] units?
b.
When you place the vessel in the water there will be [u] units of fluid displaced, which will flow into the graduated cylinder.
c.
After placing the cargo ship in the water, we now have [u] units of mass or volume left to displace.
d.
If each piece of cargo that we add to the vessel in the water is 4 units, we can place a maximum of [u] pieces of cargo in the hold of the vessel without sinking the vessel.
e. If each piece of cargo that we add to the vessel in the water is 4 units, we can place a maximum of [u] pieces of cargo in the hold of the vessel without sinking the vessel.