Answer:
displacement at 45 s = 30
65 s = 50
So the average speed over the interval from 45 s to 65 s is
(50 - 30) cm / 20 s = 1 cm / sec
As a check an average speed of 1 cm / sec for 20 sec will produce a
displacement of 1 cm / sec * 20 sec = 20 cm or from 30 to 50 cm
935,500 joules because when we use the KE formula KE=1/2mv^2;
KE=1/2(750)(50)^2
KE=375(2500)
KE=935,500 Joules
Hope it helps
Answer:
one-third of its weight on Earth's surface
Explanation:
Weight of an object is = W = m*g
Gravity on Earth = g₁ = 9.8 m/s
Gravity on Mars = g₂ =
g₁
Weight of probe on earth = w₁ = m * g₁
Weight of probe on Mars = w₂ = m * g₂ -------- ( 1 )
As g₂ = g₁/3 --------- ( 2 )
Put equation (2) in equation (1)
so
Weight of probe on Mars = w₂ = m * g₁ /3
Weight of probe on Mars =
m * g₁ =
w₁
⇒Weight of probe on Mars =
Weight of probe on earth
Answer:
Mount Rushmore is a very well built sculpture. It is visited by millions of people each year to see 60-foot tall images of the American presidents; George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Rosevelt which are carved into the Black Hills of South Dakota. Mount Rushmore has faced many controversies too. The land it was built on is sacred to Native Americans. The Sioux were also forced to leave the land, after lots of battles
Explanation:
Answer:
Line 3 has a mistake.
Explanation:
Electromagnetic waves consist of oscillations of electric and magnetic fields that oscillate perpendicular to the each other. Therefore, Line 1 is correct.
Also, the fields in an electromagnetic waves oscillate perpendicular to the direction of propagation of the wave: therefore, they are transverse waves. So Line 2 is also correct.
Electromagnetic waves, contrary to mechanical waves, do not need a medium to propagate: so, they can also travel through a vacuum. Therefore, Line 3 is wrong.
Finally, all electromagnetic waves travel through a vacuum at the same speed, called speed of light:

So, Line 4 is also correct.