Question
Just the answer please, not explanation
1. Physical quantities in the International System of Units are expressed in a base of ten. The ratio between the prefix M and the prefix m (M/m) has what value? a. 103 b. 106 c. 109 d. 109 e. 1018 2. When NASA was communicating with astronauts on the moon, the time from sending on the Earth to receiving on the moon was 1.28 s. Find the distance from Earth to the moon. (The speed of radio waves is 3.00 x 108 m/s.) a. 240, 000 km b. 384,000 miles c. 384 000 km d. 480, 000 km e. 768, 000 km 3. A railroad train travels forward along a straight track at 80.0 m/s for 1 000 m and then travels at 50.0 m/s for the next 1 000 m. What is the average velocity? a. 65.0 m/s b. 61.5 m/s c. 63.7 m/s d. 70.0 m/s e. 50.0 m/s given an initial velocity of 5.0 m/s and experiences a constant acceleration of 2.0 4. A cart is m/s2. What is the magnitude of the cart's displacement during the first 6.0 s of its motion a. 10 m b. 55 m c. 66 m d. 80 m e. 105 m
Explanation / Answer
1)a) 10^3
2) d = v*t = 3*10^8*1.28 = 3.84*10^8 m
option c)
3) average velocity = distance / time
= 2000 /(1000/80 + 1000/50)
= 61.5 m/s
option b)
4) S = ut +0.5at^2
S = 5*6 + 0.5*2*6^2
= 66 m
so option c) is correct
