Question

7. which of the following relations is correct?
(a) speed = distance × time
(b) speed = distance by time
(c) speed = time by distance
(d) speed = 1 by distance × time
8. The SI unit of speed is
(a) km/min
(b) m/min
(c) km/h
(d) m/s
9. A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The
total distance covered by the car is :
(a) 100 km
(d) 25 km
(b) 15 km
(c) 10 km
10. When a particle covers equal distances in equal intervals of time, it is said to be
(a) moving with uniform speed
(b) moving with oscillation
(c) moving with acceleration
(d) at rest
please help me​

Answer 1

Explanation:

Ans 7: speed = distance by time

Ans 8: m/s

Ans 9: 25km

Answer 2

Answer:

1. (a) speed = distance × time
2. (d) m/s
3. (ii) 25 km

Speed (s1) = 40km/h

Time (t1) = 15 mins = (15/60) hr

Distance d1 = (s1 × t1) = 40 × (15/60) = 10 km

Speed (s2) = 60 km/h

Time (t2) = 15 min = (15/60) hour

Distance (d2) = (s2 × t2) = 60 × (15/60) = 15 km

Total distance (d) = (d1 + d2) = 10 km + 15 km = 25 km

4. (a) moving with uniform speed

If a particle cover equal distances in equal interval of time, it is said to be move with uniform speed.

Explanation:

hope it helps you