# Science Help Practice

Calculate the speed of an 90,000 kg airplane with a kinetic energy of one billion Joules.

What is the mass of a car that has a kinetic energy if 4,320,000 J moving at 23 m/s?

My answer to number 1= 149.07

second one- not sure.
I looked up the internet for formulas on finding mass and speed, (ik the KE formula)
Im just stuck on these two. I looked at my lesson and it had no explanation, only on finding KE

1. 👍 1
2. 👎 0
3. 👁 443
1. 1. 0.5M*V^2 = KE.
0.5 * 90,000 * V^2 = 1*10^9 J. V = ?.
V = 149.07 J.

2. Use same formula as #1:
0.5M*V^2 = KE.
0.5M * 23^2 = 4.32*10^6 J. M = ?.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Science

A 54-kg jogger is running at a rate of 3m/s. What is the kinetic energy of the jogger. A. 18 Joules B. 81 Joules C. 162 Joules D. 243 Joules

2. ### physics

the speed of the fastest pitched baseball was 45 m/s, and the ball's mass was 145 g. (a) What was the magnitude of the momentum of this ball, and how many joules of kinetic energy did it have? (b) How fast would a 57 gram ball

3. ### science

Which type of mechanical energy do the following contain? Kinetic Energy, Potential Energy, or Both A Car traveling at 100 mph along a flat road - KE A rubber band that has been stretched - PE A bowling ball rolling down a lane -

4. ### physics

A skier of mass 70kg is pulled up a slope by a motor-driven cable. The acceleration of gravity is 9.8m/s^2. How much work is required to pull him 60m up a 30.7º slope (frictionless) at a constant speed of 3 m/s? answer in units

1. ### science

A 70-kg man is walking at a speed of 2.0 m/s. What is his kinetic energy (energy is measured in Joules)?

2. ### Physical Science-Can someone check my answers?

1) The kinetic energy of an object depends on which of the following? A. the object’s mass and direction B. the object’s speed and mass---------- C. the object’s work and direction D. the object’s speed and work 2) In the

3. ### Astronomy

We can calculate the kinetic energy of any moving object with a very simple formula: kinetic energy = 1/2 mv^2 ,where m is the object's mass and v is its velocity or speed. Table Energy Comparisons shows that metabolizing a candy

4. ### physics

you and a flight attendant toss a ball back and forth in an airplane in flight. Does the kinetic energy of the ball depend on the speed of the airplane? Defend you answer.

1. ### Science

How would the kinetic energy of a 12,000-kg train compare with the kinetic energy of a 900-kg compact car of both were traveling at the same speed?

2. ### 8th grade physical science

You are on roller blades on top of a small hill. Your PE is 1,000.0 Joules. The last time you check your mass was 60.0 kg. What is the height of the hill? if you start skating down this hill, your poetntial energy will be

3. ### Economics

The value of the marginal propensity to save is 0.2. If real GDP increases by \$50 billion, this situation was the result of an increase in the aggregate expenditures schedule of: a. \$10 billion b. \$15 billion c. \$16 billion d. \$40

4. ### Physics

1. Calculate the kinetic energy of a 5.2kg object moving at 2.4 m/s 7. Calculate the potential energy of a 5.2kg object positioned 5.8m above the ground 21. Calculate the speed of a 5.2 kg object that possesses 26.1 J of kinetic